The combined market cap of BT 500 companies continues its sharp upward trajectory

*1993-96: market value of financial year ended March used to calculate the total for top 500 companies. 1997-2001: average market cap between April 1 and March 31 used. Since 2002: average market cap between April 1 and September 30 used. From 2015, average market cap for OctSept period used. Before 2011, state-run companies were listed separately