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House of Lords - Inquiry into use of the RPI

  • 1.  House of Lords - Inquiry into use of the RPI

    Posted 12-06-2018 12:29

    New inquiry launched into use of RPI as a measure of inflation

    12 June 2018

    The Economic Affairs Committee launches its short inquiry into the use of RPI with two evidence sessions. Witnesses will be asked if we should stop using the Retail Price Index (RPI) as a measure of inflation, what reasons are there for keeping it, and what impact would changing RPI have on the people and organisations who use it.

    Background to the inquiry

    Following comments to the Committee by the Governor of the Bank of England in January 2018 that it may be time to transition away from using the retail price index (RPI), as referred to in the Committee's most recent report, Treating Students Fairly: The Economics of Post-School Education, the Economic Affairs Committee of the House of Lords is conducting a short inquiry into the use of RPI. It will conclude before the summer recess.


    Tuesday 12 June in Committee Room 1, Palace of Westminster
    At 3.35pm

    • Chris Giles, Economics Editor at the Financial Times
    • Paul Johnson, Director of the Institute for Fiscal Studies (IFS)

    At 4.35 pm

    • Jonathon Athow, Deputy National Statistician and Director General for Economic Statistics at the Office for National Statistics (ONS)
    • Sir David Norgrove, Chair of the UK Statistics Authority (UKSA)

    Likely questions

    • What are the differences between how RPI and CPI are calculated?

    • What are the arguments against scrapping RPI altogether?

    • How much could the Government save in reduced debt interest payments if it switched index-linked gilts onto CPI?

    • Do you agree with the Chancellor of the Exchequer that moving from RPI to CPI will have a physical cost and will shift the burden of taxation between different groups of taxpayers? Who will be the winners, and who will lose out?

    • Why do you think RPI is "a poor measure of inflation"?

    • In the ONS's March 2018 paper on RPI, the National Statistician said that a reason for not changing RPI was that some users valued the continuity of the index, despite its flaws. Can you explain why you think it is more important for a statistic to be consistent than correct

    • Can you explain the process for making changes to RPI?

    • What would you like to see happen to RPI?

    Further information

    Tony Cox
    chair, RPI CPI User Group

  • 2.  RE: House of Lords - Inquiry into use of the RPI

    Posted 12-06-2018 16:25
    Hi Tony and thanks for this.

    I only became aware of this earlier via social media ( which shows it does have a use...). I contacted the Lords Committee to invite them along tomorrow and here is a salient section from my email.

    "Accordingly I am making contact for two reasons. Attending the event would give your members exposure to a much wider range of expertise on the subject of the RPI than the limited group you have today. Also it will help you with the subject of balance as the four speakers you will be listening to today are all against the RPI with some being very strongly so. This gives a very unbalanced view of the ongoing debate on the subject."



  • 3.  RE: House of Lords - Inquiry into use of the RPI

    Posted 13-06-2018 13:18
    Hi All

    The House of Lords Economic Affairs Committee have replied promptly and here is the main part.

    "Thank you for your email yesterday, and for your kind invitation to the Committee. Yesterday was only the first set of sessions for the inquiry, and we have a session next week which we expect the arguments in the other direction to come to the fore.


    Staff to the Committee will be in attendance this evening, and we have emailed the details to the members: the unfortunate short notice and the busy parliamentary schedule currently means it may be unlikely for them to attend. We will report back to them on the event nevertheless."


    I look forwards to meeting them later.




  • 4.  RE: House of Lords - Inquiry into use of the RPI

    Posted 18-06-2018 15:12
    Edited by Shaun Richards 18-06-2018 15:13
    Hi All

    I have replied again to the Economic Affairs Committee because of a new development. Many of you will be aware that the RPI is criticised due to its use of house prices. However the President of the European Central Bank Mario Draghi has given the opposite view in correspondence to an MEP published on Friday.

    "As also indicated in its Opinion on the HICP Framework Regulation5 , the ECB has been, from a conceptual point of view, in favour of the inclusion of an owner-occupied housing price index in the HICP, since the index's coverage of household expenditure for consumption purposes could be improved"

    This does pose a serious question as of course the UK CPI is a copy of the European measure. Indeed this was one of its purposes.


    Shaun Richards


  • 5.  RE: House of Lords - Inquiry into use of the RPI

    Posted 21-06-2018 18:58
    It seems to me that the witnesses at the Economic Affairs Committee's RPI hearings are completely biased. Chris Giles is an anti-RPI fanatic, for reasons one can only guess at. Paul Johnson is usually fair minded but seems to have been got at over RPI. Many of us will have been at the presentation he gave on his report. Someone there pointed out that many statisticians disagreed with his conclusions about RPI. He said "not the ones I talk to". Since it was clear he had been principally talking to ONS this was hardly surprising but did not show unbiased judgment on his part. The other tow witnesses are distinctly establishment. Why did they not ask Dr Courtney, for example. It is clear to me that RPI over-estimates by a small amount. It is equally clear that CPI underestimates by a large amount. This just looks like another stitch up.
    David Quinn

  • 6.  RE: House of Lords - Inquiry into use of the RPI

    Posted 22-06-2018 04:31

    David, I agree with you about the witnesses on January 12, who were uniformly poor.  The witnesses the week after were much better, particularly Simon Briscoe. They all seemed to agree that there was a need for at least two consumer price series, a household-oriented measure and a macroeconomic measure. The first four all seemed to be looking for one index to rule them all and in the darkness bind them. For example  David Johnson  said: "…there is no particular reason for using RPI and CPI in different cases. There is no argument there." I don't think Dr. Courtney was the witness I would most have liked to have seen instead of the first four, although he certainly would have provided a corrective to the absolute dismissal of the use of the Carli formula by the witnesses. I was particularly disappointed in Chris Giles as he mentioned the Dutot formula in his testimony but seemed to have no problem with it. I suspect it is still too much used in the UK consumer price series, even though it can generate noisy series as compared to the Jevons particularly for luxury goods. He seemed to understand that well enough when he was a member of the CPIAC. Now he seems to have forgotten all about it.


    The HCIs didn't come up at all on January 12, as they surely would have if John Astin, Jill Leyland, or Helen Sands had been called on to testify.  Shaun Richards would surely have pointed out that the case for moving from RPIX to the UK HICP as the Bank of England's target inflation indicator was weak, and that it implicitly meant an increase in the target rate of inflation. Also, the Lords would not have been misinformed about the treatment of owner-occupied housing in the RPI, if I had been a witness. It was absurd to say that the accounting approach to OOH used in the RPI was some kind of muddled mix of the payments and user cost approaches. It is a separate variant of the user cost approach, distinct from the opportunity cost approach. It was disappointing that neither of the witnesses from the UKSA seemed to be aware of this. I doubt that it would be good value for the UK taxpayer but I would be happy to appear as a witness before the inquiry if the UK government would pay my travel expenses.


    Best regards,



  • 7.  RE: House of Lords - Inquiry into use of the RPI

    Posted 23-06-2018 11:07
    There was one particular issue which was I think not mentioned at all in these sessions, and that is the future status of the CPI. Everybody seemed to be assuming that this is THE index which will stand forever as a steady beacon. But let us not forget that the UK CPI is the EU's HICP, and the future development of the HICP will be out of the UK's control after Brexit. Is that acceptable to the government and the Bank?

    John Astin

  • 8.  RE: House of Lords - Inquiry into use of the RPI

    Posted 24-06-2018 06:25

    Eventually, people will realise tht there should be an owner-occupied housing component.  Whether or not they accept the way it is done in the CPIH or the RPI, eventually something will have to be done about that.

  • 9.  RE: House of Lords - Inquiry into use of the RPI

    Posted 22-06-2018 16:51
    Unfortunately the current establishment is opposed to the arithmetic mean and pro the geometric mean.

    They are living in the wisdom of 40 years ago, which has now been shown to be wrong.


  • 10.  RE: House of Lords - Inquiry into use of the RPI

    Posted 06-07-2018 13:18

    House of Lords Economic Affairs Committee Call for Evidence


    Today I received an email from the secretariat to the House of Lords Economic Affairs Committee with a Call for Evidence for their inquiry "The use of the retail price index (RPI)".


    Some user group colleagues may have received a similar email.


    The link to this call for evidence is at https://www.parliament.uk/business/committees/committees-a-z/lords-select/economic-affairs-committee/news-parliament-2017/rpi-inquiry-launch/


    The pdf document included amongst the call for evidence documentation states –


    "We are looking to hear from as diverse a range of views as possible-if you think someone you know would have an interest in contributing to the inquiry, please do pass this on to them."


    User group colleagues may wish to submit evidence.


    All the best.



  • 11.  RE: House of Lords - Inquiry into use of the RPI

    Posted 08-07-2018 00:39

    Dear Arthur:

    Thank you for this. I hadn't received the e-mail you did but on your advice I had already written to the secretariat for the Committee. It seems they are quite serious about not accepting documents not prepared strictly for the inquiry, as I found out. I think the restrictions on length of submissions are quite strict considering the complexity of the issues involved and the small number of people who would likely bother to write something.

    I just added a document to the library that is essentially a comment on the testimony on the RPI issue before the Lords Committee thus far: "The RPI Follows an Accounting Approach, Not a Blended Approach, to Owner-Occupied Housing Costs". I would like to thank Gemma Keane of ONS for valuable information about transaction costs in the RPI. I also made very minor changes to a previous paper I had written about the same subject two years ago, which is also in the library. The changes in no way attempt to remove evidence of the not very great evolution in my views since I wrote the original paper. My new paper much exceeded the limit for submissions for this inquiry even though it only deals with a small part of the topic. I really do think that submitters are not being given enough space to express their views.

    Good luck with your own submission if you are writing one.

    Best regards,



  • 12.  RE: House of Lords - Inquiry into use of the RPI

    Posted 08-10-2018 12:13

    Just to let User Group colleagues know that the Economic Affairs Committee hears from Deputy Governor of the Bank of England, Dr Ben Broadbent this Tuesday 9 October 2018 at 3.35pm.



    Likely questions

    • Is the consumer price index (CPI) a good measure of general household inflation?
    • The Governor of the Bank of England told the Committee in January that the way housing costs were implemented in the RPI was a known error with the index. Why is this the case?
    • Does the Bank of England accept that different price indices are required for macroeconomic purposes and cost of living purposes?
    • Which of the household cost indices being developed is the best solution for a cost of living index?
    • What is the role of the Bank of England in determining whether a change to RPI would be materially detrimental to the interests of gilt holders and the factors which the Bank would take into account?


    Colleagues may also be interested that on the investigation home page it says –


    "The deadline for written submissions has now passed. Contact the Clerk if you still wish to make a submission. Oral evidence ongoing."


    There have been about 40 written submissions to date and I will admit to having only read a small fraction of them.


    All the best.



  • 13.  RE: House of Lords - Inquiry into use of the RPI

    Posted 10-10-2018 16:44

    Doubtless some colleagues will have seen the House of Lords RPI Committee evidence from the Bank's Deputy Governor yesterday.

    I have to say I was surprised and indeed rather shocked at the Deputy Governor's statements about the Household Costs Index (HCI). He does not follow John Pullinger's opinion that the CPI (and CPIH) are "macroeconomic" indices as compared with HCI as a microeconomic  household-based index. Indeed, he said that there can only be a single "best" measure of consumer price inflation.

    I had the feeling that he suspects the HCI somehow to be a competitor of the CPI – and perhaps a threat to it. This is of course nonsense. In our paper "Towards a Household Inflation Index" (2015), Jill Leyland and I clearly presented the HII as a separate index from CPI and with a separate purpose – in fact a purpose in line with the origins of consumer price indices, focussed on inflation as experienced by households. The Deputy Governor said several times that he was unclear what the meaning of "households' experience" was. I imagine he has not read our paper!

    He went on to give as an example the treatment of interest payments, referring, in the now familiar manner of dyed-in-the-wool national accounts-oriented economists, that interest received and interest paid are merely two sides of the same coin – one is a plus and the other a minus - and neither should be included in a CPI. He does not seem to appreciate that from the point of view of the household, interest – and especially mortgage interest -  is a major outgoing. Interest does indeed have a price: the rate of interest, and a rise in that rate represents inflation for the home-owner. My experience of householders' attitudes to interest-in and interest-out is that if they get a windfall of cash their first priority is to pay off some of their mortgage rather than invest it in a bank deposit. But for the Deputy Governor all this is seen as nothing more than a matter of "semantics" and "language". It is actually far more serious than that.

    The Deputy Governor also surprised me with his reference to the lack of an OOH measure in the HICP/CPI. He did not appear to know that the decision to measure OOH in the HICP was taken many years ago (in fact when I was still leading the development of the HICP) – including the decision on how to calculate OOH on the basis of net acquisitions,  i.e. mainly new housing plus acquisitions from other sectors. Most if not all EU countries (including the UK) are now producing such an index, and it seems to be only a matter of time before it will be included in the HICP/CPI. Presumably that will then be a trigger for the Bank to move to CPIH instead of CPI.

    John Astin

  • 14.  RE: House of Lords - Inquiry into use of the RPI

    Posted 11-10-2018 09:25

    Obviously, across the economy as a whole interest in must equal interest out.  This is irrelevant to any sensible measure of consumer inflation, for two reasons:

    1. For consumers, interest in does not equal interest out.  At the very least, the net outflow of interest from this sector must be considered.
    2. Interest in is generally perceived as income, although from a macroeconomic perspective it is not.  Would anyone regard a rise in incomes as a reduction in inflation?

    A very rough parallel may be drawn with insurance premiums.  Their weight in the CPI is net of reimbursements from insurance companies.  However, it is the gross premium that is the measure of cost.

    Michael Baxter

  • 15.  RE: House of Lords - Inquiry into use of the RPI

    Posted 10-10-2018 17:11

    Dear Arthur:

    Thank you very much for telling us about Ben Broadbent testifying before the House of Lords Committee.

    One would expect a Deputy Governor of the Bank of England to be much better informed about inflation measures than he was. He spoke about Eurostat taking a long time to decide how they would incorporate owner-occupied housing in the HICP. This is completely false. From March 1997 forward, the only option that Eurostat has entertained has been an OOH price index based on the net acquisitions approach. It is strange that Mr. Broadbent would say this, as the UK has been part of all four Eurostat OOHPI pilots, starting in 2000. The big impediment to its introduction in the HICP has always been data related. By December 31, less than 12 weeks from when Mr. Broadbent testified, Eurostat must publish a report on incorporating OOHPI in the HICP. If it doesn't establish a timeline for adding OOHPI to the HICP, it will almost certainly be for data-related reasons. Lord Lamont, who as Chancellor of the Exchequer, introduced inflation targeting to the Bank of England, asked Mr. Broadbent if it was important that the inflation indicator used be consistent with international practice (as I recall) and was almost certainly thinking about this forthcoming Eurostat report. Mr. Broadbent said it wasn't, but gave no indication he was aware of the report.

    Even as a dumbed down version of the existing RPI approach to OOH, Mr. Broadbent's description was inadequate. He implied that the only components included in the RPI were mortgage interest and depreciation. He rejected mortgage interest being in any kind of consumer price series on the absurd ground that the counterpart of mortgage interest paid was interest received by savers, but he would not, presumably, exclude haircuts from a consumer price series on the grounds that the counterpart of spending on them is income to the hair stylist. Mr. Broadbent much prefers imputed rent as a measure of OOH costs, but seemed to have no awareness that conceptually imputed rent covers off both mortgage interest and depreciation, those components he dislikes, as well as dwelling insurance, ground rent, owner repairs and DIY materials, the RPI components he chose to ignore. Imputed rent does not cover off RPI components for estate agents' fees and other real estate transaction costs, which are not part of consumption expenditure in a national accounting sense. Presumably, Mr. Broadbent does not support their inclusion in a consumer price series, but it is a pity that Lord Lamont didn't get him to explicitly say so. The Eurostat OOHPI is supposed to include all transaction costs, including stamp duty, which is omitted from the RPI.

    When Mr. Broadbent was asked to confirm or deny that the OOH component in the Irish CPI was just an index of interest costs, he professed he didn't know. A mortgage interest CPI is in fact the only OOH component in the Irish CPI, based on current variable mortgage rates and a 20-year moving average of house prices, so it is quite similar to the mortgage interest component that Mr. Broadbent denounces in the RPI. Ireland is the only country with which the EU shares a land border, so you would think that Mr. Broadbent would have at least a basic idea of how the Irish CPI is measured. Possibly he does, and simply did not want to admit that the Irish CPI, unlike the UK CPI, directly incorporates changes in house prices.

    Thank you again, Arthur.


  • 16.  RE: House of Lords - Inquiry into use of the RPI

    Posted 16-10-2018 17:22

    I waited until the text of Dr Ben Broadbent's evidence was published before posting as I wasn't sure whether or not he had conflated two different versions of time reversal. I suspect that Dr Broadbent has done so but what he meant is not entirely clear –


    Page 8
    "As to the faults in the RPI and its index, one of my economists handed me a pamphlet by Irving Fisher from 1920 which pointed out how poor the Carli weighting measure was."

    Page 10
    "Therefore they are not returning and not having zero average inflation across the two periods…"


    The brief thoughts below are not intended to be rigorous –

    1. The Fisher version is essentially that a price index should be symmetric in time.


    1. The second version is that a set of prices can reoccur in the future.


    The Fisher version implies that time can flow both forwards and backwards. This does not fit with our experience of time and is analogous to the sci-fi world of, say, Dr Who. It is also not consistent with the physics of the second law of thermodynamics.


    There is no reason why an index formula should not be symmetric in time – most theories in physics are symmetric in time – but arguably it is unreasonable to condemn Carli because it follows the second law of thermodynamics and is not symmetric in time. Why should a decision on the choice of index formula be dependent on a phenomenon that will not be observed in the real world?


    Also from an algebraic perspective the Fisher version involves the inversion of a price relative and because Carli is implemented in the RPI with a base month the denominator must always remain the base month price. Arguably inverting a price relative is not meaningful in the RPI context.


    The second version does fit with our experience. Sets of prices can return to their earlier values and in that case the expectation is that the index should also return to its previous value. All three elementary aggregate indices – Carli, Jevons and Dutot – satisfy this version if only because they use a base month to calculate the indices.


    In reality most price indices are more complex and, for example, quality change and chain linking affect outcomes. If there is a non-comparable replacement then a new base month price is imputed. This implies that if the same set of prices reoccurs after a non-comparable replacement then because the base month data has changed the index does not revert to the previous value – all the elementary aggregate formulae in the RPI and CPI are similarly affected. This can be interpreted as the prices are the same but the basket has changed.   The process of chain linking has similar implications but it is far less likely that the larger number of prices involved would all return to the same values.


    To conclude the criticism made by the deputy governor of the use of Carli within the RPI is unconvincing at best.


    All the best.




    Link to text version of Dr Ben Broadbent's evidence



  • 17.  RE: House of Lords - Inquiry into use of the RPI

    Posted 17-10-2018 15:33
    Hi Arthur and thank you for drawing my/our attention to this.

    Those who just follow the statistics may be unaware of Dr.Broadbent's position which is of someone who was moved from an external role to an internal role at the Bank of England. I am far from alone in being worried about the moral hazard of such a move which as a by product has a remuneration scheme of around £200,000 per annum higher and of course also for considerably longer. Also being an internal member of the Bank of England brought membership of the pension scheme which does not share the institution's stated view on the RPI. In fact I am struggling to think of any organisation more enthusiastic about the RPI in investment terms than it.

    If we skip the early part of the evidence where Dr. Broadbent finds it more comfortable to answer different questions to the ones actually asked, we arrive at this. Here is his view of those who own their own house.

    "What they are really doing, in an economic sense, is acting as both landlord and tenant of the same property."

    Those who have bought their own house to avoid being a tenant may be worried at first. But hopefully they will soon realise that it is the absent minded professor who is confused. If you follow his past record then you will be aware he often seems confused. There are two main  problems with his argument below.

    " there are fewer than 10 million owner occupier mortgages. Is the cost of a house to someone who happens
    already to have paid off his or her mortgage really zero?"

    So we see that we cannot use something which is used around 10 million times but we can use the Imputed Rents which are used precisely zero times! I do not recall anyone arguing for mortgage costs to be used for those who do not have one, in the way he is calling for rents to be used for those who do not pay them. For example the RPI has mortgage costs, but also as a considerably larger component house prices  via  the use of depreciation.

    As to the use in practice even Dr.Broadbent cannot dodge the serious problems.

    "it is not an entirely straightforward task to construct rental equivalence series for owner occupied
    housing.............There were some teething problems in getting at the rental equivalent in the early days of CPIH. It has now settled down
    reasonably well. "

    By "teething problems" he means that there was what is one of the worst problems in statistics which is a discontinuity.  As to reasonably well I know other members on here remain unhappy with it.

    Let me end by congratulating the Lords and Baroness Bowles on pressing the Deputy Governor responsible for the RPI on the issue of what Yes Prime Minster satirised as "Masterly Inaction". As they point out there are changes which could have been made as opposed to the state of play during his tenure.

    "That process seems to have stalled."


    Shaun Richards


  • 18.  RE: House of Lords - Inquiry into use of the RPI

    Posted 18-10-2018 10:02

    Thank you Shaun for your useful post today. It seems that the initial post which I made after the Broadbent session has become detached from the current HoL thread. I don't know if anybody can sew it back in?


    John Astin

  • 19.  RE: House of Lords - Inquiry into use of the RPI

    Posted 18-10-2018 03:03

    Dear Arthur:

     I have added a document to the library on the same subject as yours, the inquiry into the use of the RPI. Thank you again for your help with it.

    Best regards,


  • 20.  RE: House of Lords - Inquiry into use of the RPI

    Posted 17-01-2019 10:40
    The House of Lords Economic Affairs Committee has today published its report, "Managing Inflation" following its inquiry into the use of the RPI.  The full report can be found at -


    Tony Cox
    chair, RPI CPI User Group

  • 21.  RE: House of Lords - Inquiry into use of the RPI

    Posted 17-01-2019 16:22
    The following article on the BBC News web site provides a commentary on the House of Lords Committee report – https://www.bbc.co.uk/news/business-46897541

    I leave colleagues to make up their own minds but I will admit to being disappointed at the balance of the article.

    All the best.


  • 22.  RE: House of Lords - Inquiry into use of the RPI

    Posted 17-01-2019 22:43
    Hi All

    I think that we should welcome this report from the House of Lords as to their credit they have slayed two inflation measurement dragons.

    1. Rental Equivalence as its supporters may now  struggle to fill a phone box.
    2. The Formula Effect via the route of reforming the collection of prices in the clothing and especially fashion clothing sector.

    I think that it also reflects well also on the Royal Statistical Society and this User Group as it may have taken time but we have got an official acknowledgement of the major problems that the ONS, Bank of England and the OSR have tried to sweep under the carpet. Accordingly it has been a bad day for them.

    Moving onto the media I am sorry to say that the article on the BBC Website quoted by Arthur Barnett may be the worst but is not alone. I have done my best to explain things to the more City based media and that is all we can do. After all those of you who recall the campaign of Chris Giles of the Financial Times against the RPI including speaking at the RSS in 2012/3 may be a bit bemused by some of the coverage there.

    But the important thing is that we have made progress on the major issues and for people's benefits,wages and pensions that really matters.

    More detail can be found on my blog


    Shaun Richards


  • 23.  RE: House of Lords - Inquiry into use of the RPI

    Posted 18-01-2019 14:57
    Hetan Shah has, as would be expected, written a much better and very concise summary for CityAM – http://www.cityam.com/271822/lords-have-spoken-its-time-fix-rpi-and-reform-way-we

    All the best.


  • 24.  RE: House of Lords - Inquiry into use of the RPI

    Posted 18-01-2019 15:19

    Yes – an excellent and well-focussed note by Hetan.


    John Astin


  • 25.  RE: House of Lords - Inquiry into use of the RPI

    Posted 18-01-2019 18:17
    I must say I am puzzled by the Lords review outcome and by some of the comments here. I have not read the whole report but the summary seems somewhat naïve. Some of the recommendations are to be welcomed - that Rental Equivalence is as Shaun says for the birds and that ONS should do their job rather than running away. But this para shows little understanding of the RPI/CPI differences
    "The UK Statistics Authority has admitted that there is a problem with the RPI. The problem is an unintended consequence of a routine methodological improvement to the collection of price quotes for clothing. It has caused the 'formula effect'-the difference in the annual rate of change in the RPI compared to the CPI due to the way in which price averages are calculated- to widen: the gap was around 0.5 percentage points before 2010, the year the change was made, and it has been around 0.8 percentage points since."

    Surely the clothing issue is not the main reason for the formula effect. The formulae are. There is no mention of the Economic argument for Jevons being unproven at best and opportunistic at worst. Unlike Johnson they don't seem to have been unduly influenced by the people they talked to (I fear Johnson, for whose views I normally have a lot of respect, was like James I in this instance - James was called the royal cushion - he bore the imprint of the last person who had sat on him - actually I think this was unfair about James who was a clever and energetic man). If you remember when asked at the presentation of his report whether he realised that many statisticians did not agree with the whole CPI rectitude he said dismissively "not the ones I talk to".

    My assessment of the general position of the group through the years of this is that very roughly while there is an upward bias in RPI it is nowhere near as bad as the downward bias in CPI. CPIH in whatever form will not fix this.

    As you see from my demotic style I am not a statistician. I have a 40 year old degree in Economics with some statistics, so I have been able to keep up with the general arguments without understanding the deeper technicalities. I do feel though that this Lords Review reveals a shallow understanding of the problem. Large numbers of current and future pensioners have lost huge amounts of money through the adoption of CPI which as John Astin has often pointed out is not a proper measure of cost of living and was never meant to be. I am afraid this is yet another missed opportunity to question the government's cynical money-saving espousal of CPI (not to mention its cherry picking of RPI when it took its fancy).

  • 26.  RE: House of Lords - Inquiry into use of the RPI

    Posted 21-01-2019 12:45
    Hi David

    I have some extra thoughts for you. To my mind the major move from the House of Lords was the rejection of Rental Equivalence. This is because over time the omission of owner occupied housing costs ( CPI) and then the modification with the lowest series that could feasibly be added ( CPIH) have hurt pensioners, workers and those receiving benefits by a substantial amount. As good moves from official bodies on the subject of inflation have been to say the least thin on the ground it makes me a fan of the report.

    Looking at my post from a few days ago I got a little carried away by saying the dragon of the formula effect has been slayed. Much better would be to say that we are finally on the road where that is a possibility and hopefully a probability. Thus I am less concerned by the Carli/Jeevons debate as that can be done later to the extent that it can be done at all. as over the time that I have been involved explicitly in this which is now 7 years or so both sides have shown solidity of which even the hardest rock would be proud. Although there is a change in Carli not being outright attacked by an official report.

    Oh and on a historical note wasn't the same criticism aimed at Charles I?


    Shaun Richards


  • 27.  RE: House of Lords - Inquiry into use of the RPI

    Posted 21-01-2019 12:51
    Yes, I agree that the House of Lords report is shallow regarding the formula effect.  It actually says that "it may be a perpetual debate".  Well that is not good enough.  If two theories differ, the solution is to find data which will discriminate between the two theories.  That is also known as science.

    On the positive side, I noted a few things:

    a) the report supports a single inflation measure rather two measures as advocated by the RSS.  It also says that the RPI would be a viable candidate for such a measure.

    b) it supports inclusion of OOH costs but not via rental equivalence.

    c) it criticises the  UKSA and National Statistician for not modernising the RPI, instead of letting it wither on the vine.  It dismisses arguments about indexed gilts here and says that ONS should stick to its remit on quality of statistics, and keep out of politics.

    d)  it supports convergence of existing measures of inflation on to a new single measure of inflation.

    e)  it notes that the last issue of indexed gilts with an RPI undertaking expire in 2030 and not 2068 (which is the last IG issue on the market).


  • 28.  RE: House of Lords - Inquiry into use of the RPI

    Posted 3 days ago
    Hi All

    I thought it would be helpful to point out some changes in the current inflation environment which have been highlighted by today's data set. One development which raises some wry humour is the way that the gap in February between CPI and RPI is 0.6%. That is around half of what we have seen in recent times and also less than the official estimates of the "formula effect" gap between the two which is usually expressed as 0.7%.

    The official explanation continues the theme of trying to promote the CPIH measure which as I am sure you are all aware is widely ignored once we move outside the paperwork promoted by ONS.

    "The difference between the CPIH and RPI unrounded annual rates in February 2019 was -0.67 percentage points, narrowing from -0.77 percentage points in January 2019.

    The main factors contributing to the narrowing were:

    • Other housing components, which decreased the RPI 12-month rate relative to the CPIH 12-month rate by 0.07 percentage points between January and February 2019. The effect came mainly from house depreciation.

    • The formula effect, which decreased the RPI 12-month rate relative to the CPIH 12-month rate by 0.03 percentage points between January and February 2019. The effect came mainly from clothing and footwear."

    So we see that the situation is one which has quite a wide standard deviation.


    Shaun Richards


  • 29.  RE: House of Lords - Inquiry into use of the RPI

    Posted 3 days ago

    Dear Shaun:

    Thank you for pointing this out. The formula effect as measured by the difference between the RPI and the RPIJ has also gone down. It was -0.7% in December, but has been -0.6% for the last two months. Since the RPI inflation rate in February was 2.4%, unchanged from January, this means that the RPIJ inflation rate was 1.8%, unchanged from January. If the ONS has refined its methods in ways that permanently reduce the formula effect, it would be a welcome development, but the series has had its ups and downs in the past.

    Even though the inflation rates for components like housing depreciation and dwelling insurance have come down a lot the RPIJ inflation rate still exceeds the CPIH inflation rate. In fact, to find a period when the RPIJ inflation rate was below the CPIH inflation rate for more than a couple of months one has to go back to the period August 2008 to December 2009, i.e. the time of the financial crisis.

    In fact, the CPIH inflation rate is only as high as it is because of the decision, inexplicable on the face of it, to incorporate council tax in it. Council tax only changes once a year in April, so is still registering a 4.9% annual inflation rate, its highest since March 2005. The CPIH inflation rate excluding council tax would only be 1.7% in February, up from 1.6% in January and it would be really hard to sell an inflation rate so much lower than the alternatives as the headline measure.

    On March 5, in his testimony before the House of Lords Economic Affairs Committee, Governor Carney would have us believe that he  favoured an inflation measure that represented consumption pur et dur, and CPIH is that kind of measure. But it obviously is not: the scope of consumption expenditures in the National Accounts doesn't include council tax any more than it includes the real estate transaction costs whose presence in the RPI Governor Carney finds inappropriate. (He never questioned their presence in the Canadian CPI.)

    The ONS should replace the CPIH with the RPIJ as the deflator of nominal wages. In the long term, a monthly Household Inflation Index would be the optimal deflator, but the ONS still seems to be a long way from turning the experimental HCIs into such an index.

    Best regards,