City of Oxford Warrants is fifth out of 522 investment trusts with growth of 200 per cent in the year to December 5.
But the split-capital trust, managed by Chris Burvill, is ranked 425th out of 433 over three years.
The secret of its recent success has been gearing, enabling ordinary shares to leap sixfold for any single unit rises, claims the fund manager.
The £46.9m fund has 26.2 million ordinary shares and 30.1 million preference shares.
About 55 per cent of the investments are held in FTSE-100 blue-chip firms while 20 per cent are held in small companies and 10 per cent in mid-size firms. About 10 per cent of funds are held in cash and 5 per cent in property.
Burvill says: "It is an incredibly highly geared fund offering 6:1 returns on income growth. It is aimed at the professional investor."