The index is owned and calculated by the Financial Times, this index is based on the prices of 30 leading industrial and commercial shares and is calculated hourly during the day with a closing index at 4.30 p.m.
The FT 30 index was first published by the Financial News in 1935. In fact, five of the original constituents of the FT 30 are still constituents. The index is un-weighted, i.e. all shares are counted equally. This introduces some difficulties in using it as a measure of long-term portfolio performance. The FT-Actuaries All-Share Index was launched in 1962 and introduced weightings by market capitalization.