Inflation is a key macroeconomic variable and governments typically aim for both low and stable rates of inflation. In the UK there are two main measures of the rate of inflation in the UK – the CPI and the RPI. Over the past few years there has been a growing gap between the two measures and this has led to consultations about how the RPI could be adapted to allow it to rise more slowly in the future. (Click here for a PowerPoint of the chart.)
The RPI and CPI measure inflation in different ways – they don’t measure the same basket of goods. The RPI measure includes the costs of housing, whereas the CPI does not include this. Furthermore, the RPI is an arithmetic mean and the CPI is a geometric mean, which will be lower than the arithmetic mean. The ONS says that a key advantage of using the geometric mean (i.e. the CPI) is that:
…it can better reflect changes in consumer spending patterns relative to changes in the price of goods and services.
Typically the RPI has been about 1% higher than the CPI and governments can benefit from this by linking state benefits to the CPI (the lower rate) and payments they receive to the RPI, thus maximising the difference between earnings and expenditure.
However, the gap between these two measures of inflation has been growing and this has been causing concern for the ONS and the Office for Budget Responsibility (OBR). This has led to the consultative process regarding making changes to the RPI. However, any change made to the RPI would put certain groups at a disadvantage. One such group is pensioners – many pensioners in the private sector have their pensions linked to the RPI and if a change were made to bring it more in line with the CPI (i.e. lower it) they would suffer. Ros Altman, director general of SAGA said:
After 30 years of retirement, someone who receives 0.6% lower inflation uprating will end up with a pension nearly 20% lower…Therefore, over time, pensioners will be able to afford less and less and pensioner poverty will increase once again.
There would be some beneficiaries of any change to the RPI – the government would benefit in some areas; company pension schemes might also see gains made; some students might benefit and even rail travellers.
An announcement was made by the National Statistician, Jil Matheson, on the 10 January. Much to the surprise of most experts, she has decided to keep the RPI measure unchanged. She did recommend, however, that a new index be introduced that would be published alongside RPI and CPI. The new index would better meet international standards.
The following articles look at the arguments for and against changing the RPI measure.
Articles prior to announcement
Pensioner backlash expected over pension reform The Telegraph, Philip Aldrick (9/1/13)
Inflation: Changes to the calculation of RPI expected BBC News (9/1/13)
RPI review ‘may hit pensioners’ Express and Star (9/1/13)
Q&A: Inflation changes BBC News (9/1/13)
Pension holders and savers: beware of an RPI inflation change The Economic Voice (9/1/13)
Pensioners and savers face ‘stealth attack’ on their income from change to the inflation index Mail Online (9/1/13)
Articles following announcement
Relief for pensions as ONS says leave RPI unchanged The Telegraph (10/1/13)
RPI review recommends new inflation index The Guardian (10/1/13)
Inflation: No change to RPI calculation BBC News, 10/1/13)
The ONS puts consistency first BBC News, Stephanie Flanders (10/1/13)
Q&A: Inflation changes BBC News (10/1/13)
Announcement by National Statistician
National Statistician announces outcome of consultation on RPI ONS (10/1/13)
- How are the RPI and CPI measured?
- Why is the RPI typically higher than the CPI?
- What changes to the RPI were suggested? What are the advantages and disadvantages of each?
- Who would have benefited from each of the proposed changes to the RPI?
- Who would have suffered from each of the proposed changes to the RPI?
- Why has there been a growing divergence between the two measures of inflation?
- Do interest rates affect the RPI and CPI measures of inflation to the same extent?
- Which measure of inflation is used for the Bank of England’s inflation target? Has it always been the measure used?