As of 2017 the reference year is 2015=100. Rates of change calculated from the 2015=100 series may differ from previously published rates of change where reference year differs. The deviations are mainly due to rounding effects. See the completed time series 11446 for published rates of change figures through 2016 with 1998=100. As of January 2016, EUROSTAT's consumer classification (ECOICOP) is applied - an extended classification at the detailed level.
Consumer Price Index (weights)
The weights does not always sum to 1000.0 due to rounding effects. As of January 2011, the CPI weights are based on the National Accounts. The weights up to July 1999 were based on an old consumer classification, as of August 1999 COICOP was introduced as a new international classification. The weights after old classification were regrouped, hence no direct comparison can be made for weights between the period 1979-July 1999 and as of August 1999.