GDP figures are “under almost constant revision”, says The Economist, and the process can last decades. In 1960, the official UK figure for growth in 1959 was 2.7%; in 2012, 18 revisions later, it was 4.7%.
So it’s no wonder that there have been some substantial changes to quarterly GDP growth figures in the G7 states since 1994 – three years after the preliminary estimate.
The new figures usually show that the economic expansion was better than first assumed, except in the US, where the first stab is generally too optimistic. The biggest changes, up or down, have been seen in Japan.