Our commodity price indices have been published for twenty years, since the first issue of the Economic Review. They differed from the other indicators of price movements in free international markets available at that time in that their weighting system was geared to the exports of primary producing countries. This pioneering statistical exercise proved worthwhile, since these index numbers are now fairly widely used and their value, as an analytical and forecasting tool, was quickly recognised in estimating, amongst other things, the import potential of primary producing countries.