The inflation within inflation

In two recent blogs we have analysed the headache facing the Monetary Policy Committee, given the persistence of inflationary pressures in the UK economy, in deciding whether to raise interest rates. In Food for thought, Elizabeth Jones describes how, despite the weakness of aggregate demand, cost pressures have fuelled inflation while John Sloman in Time for a rise in Bank Rate looks at the difficult judgement call for the MPC in risking a marked dampening of aggregate demand by raising rates while, on the other hand, failing to dampen inflationary expectations by not raising rates. In this blog Dean Garratt analyses some of the latest inflation figures as detailed in the latest Consumer Price Indices Statistical Bulletin. In particular, he focuses on the inflation rates within the overall consumer price inflation rate.

You might be wondering what we mean when we refer to inflation rates within the overall inflation rate. In answering this we need to consider how the Office for National Statistics goes about estimating the Consumer Price Index (CPI) and the CPI inflation rate (further details are available in Consumer Price Indices – A Brief Guide produced by the ONS). In order to compile the Consumer Price Index (CPI), each month an organisation collects on behalf of the ONS something in the region of 110,000 prices quotations for around 560 items. But, the key point is that these goods and services fall into one of 12 broad product groups which are referred to as level 1 product groups. These include, for example, food and non-alcoholic beverages and transport.

The items included in each of the 12 product groups are reviewed once a year so that the chosen items remain representative of today’s spending patterns. Once the price information for our representative goods and services has been collected, the prices are compared with their levels in the previous January and the change recorded. These changes are then aggregated in both each product group and across all groups. The price changes are aggregated by weighting them according to the typical share of household spending that each good or service represents. This process is repeated each month in the year so as to always calculate the aggregate change in prices since January. The final step is to link the price changes with those from earlier years to form one long price index, both for each product group and for the overall shopping basket, so that at one arbitrary moment in time the index takes a value of 100.

Once we have our price indices we can calculate annual rates of price inflation. The annual rate of CPI inflation in December 2010 is recorded at 3.7%. This means that the Consumer Price Index was 3.7% higher in December 2010 than it was December 2009. Similarly, the annual rate of CPI inflation in November 2010 of 3.3% means that consumer prices rose by 3.3% between November 2009 and November 2010. Across 2010 as a whole the CPI rose by 3.3%, so in excess of the Bank of England’s inflation rate target range, and significantly up on the 2.2% across 2009. The Bank has a symmetrical inflation rate target of 2% plus or minus 1 percentage point (you may want to read more about the Bank’s Monetary Policy Framework).

Let’s look to delve deeper because price indices are also available for product groups at two lower levels known as level 2 and level 3 product groups. For example, from within the food and non-alcoholic beverages group there is a price index wholly for food and within this one for vegetables. Again annual rates of price inflation can be found for level 2 and level 3 product groups.

If we consider food and non-alcoholic beverages we find an annual rate of price inflation for December of 6.1%. This was its highest annual rate since May 2009. Across 2010 as a whole we find that prices rose by 3.4%, very much in accordance with the overall CPI inflation rate. Inflationary pressures within this category are not new with 2008 seeing prices rises by 9.1% as compared with 3.6% for the overall CPI inflation rate. Over the past 5 years, food and non-alcoholic beverage inflation has typically been running at an annual rate of 5% while overall consumer price inflation has been running at 2.8%.

If we now focus on food alone, we find an annual rate of food price inflation in December of 5.7%. While this is a little lower than with the inclusion of non-alcoholic beverages, it is nonetheless a full 2 percentage points above the overall CPI inflation rate. Across the year as a whole food price inflation comes in bang on 3% highlighting the extent of the inflationary pressures in more recent months. This, however, still falls some way short of the pressures seen in 2008 when food prices rose by 10.1%. If we drop to level 3 to focus on groups within the food category we find inflation rates for oils and fats of 11%, for fish of 9% and for fruit of 8.6%.

Within the 12 broad groups the highest annual rate of price inflation is currently to be found for transport where the annual rate of price inflation in December was 6.5%. Across 2010, transport prices rose by 8.3% which compares a tad unfavourably with the 0.8% increase seen in 2009. If we drop down to the level 3 groups within this category we can trace the source of the price pressures more readily. The cost of air passenger transport in December was up over 12 months by 13.5% and, you may not be surprised to learn, the cost of fuel and lubricants was up by 12.9%.

We finish by noting the only level 1 category to see prices fall across 2010: clothing and footwear. This product group saw prices fall by 1% in 2010. But, even here price pressures have emerged. Between April 1992 and August 2010 clothing and footwear consistently recorded annual rates of price deflation. Since September this has ceased with positive annual rates of inflation. The annual rate of inflation for clothing and footwear in December was estimated at 1.5%. Perhaps those socks in my bottom drawer really will have to last me just a little bit longer!

Articles

Inflation is a blip says Bootle BBC News (21/1/11)
Fuel prices could rise by 4p in April BBC News (22/1/11)
Paul Lewis: Why inflation is starting to buy BBC News (20/1/11)
High levels of inflation remains a worry for Beijing BBC News (20/1/11)
Inflation ‘biggest money worry for families’ BBC News (19/1/11)
UK inflation rate rises to 3.7% BBC News (18/1/11)
Inflation hysterics Financial Times (19/1/11)
Top investors raise alarm on inflation Financial Times, Richard Milne, Dan McCrum and Robert Cookson (21/1/11) )
Inflation hits 3.7% after record monthly increase Guardian UK, Graeme Wearden (18/1/11)
We knew inflation would be bad, but not this bad Guardian, Larry Elliott (18/1/11)
The mystery of clothes inflation and the formula effect The Economist (21/1/11)

Data

Latest on inflation Office for National Statistics (18/1/11)
Consumer Price Indices, Statistical Bulletin, March 2010 Office for National Statistics (18/1/11)
Consumer Price Indices, Time Series Data Office for National Statistics
For CPI (Harmonised Index of Consumer Prices) data for EU countries, see:
HICP European Central Bank

Questions