The original Actuaries Index was designed in 1929 and was maintained with broadly the same format and principles for more than thirty years, changes to constituents and groups being made in 1950 and 1957. Investment Policy and Index Numbers, submitted by the authors in 1956 (J.I.A. 83, 333), discussed the original index in some detail. This index was, of course, designed for manual calculation and it is remarkable that only eight years ago electronic computation was not even contemplated. In fact the word computer was never mentioned in the paper or in the discussion. With electronic facilities now so well developed the whole approach to indices is changed. The limitations, formerly imposed by manual calculation, on the size, the scope of the averaging procedures and the weighting methods, and the frequency of computation are no longer important.