Statisticians in bit of a twist over revised consumer price index
Compared with the old CPI series, the new CPI series generally shows smaller year-on-year rates of increase. This is because when the prices of various goods and services change, households tend to buy more of the goods and services with relatively smaller price increases ... to substitute those with larger price increases ...
Government news release, January 28
It happens every five years, right on schedule. Our statisticians conduct a survey of household expenditure patterns, adjust the weights of the consumer price index for it and, well, stripe me pink, inflation is lower than we thought it was.
We're there again. The change has just been made and whereas the previous calculations yielded a year-on-year rate of inflation in March of 4.57 per cent, we now get only 4.38 per cent from the new and improved way of doing things. Could have gone either way, you know, but it just happened to be lower this time. Funny how that happens.
If you say so, the statisticians will come out and tell you that it makes perfect sense. You naturally buy less of things that have gone up most in price. We're all bargain hunters, aren't we? The new weighting arrangement only reflects this.
Except that they seem have got themselves into a bit of a twist about it. In the very same news release in which this justification is made we have the acting commissioner for census and statistics, Lily Ou-yang, saying that a higher expenditure weighting for housing is 'mainly attributable to the general rise in rentals for private housing over the past five years'.