Investment trust RIT Capital reported a 2.1% increase in diluted NAV per share from 1 October 2011 to date but it cautioned that, despite recent market rises, the firm remains mindful that the risks ahead are 'glaring and global'.Diluted net asset value per share rose to 1,190.7p at 31 January and most recently NAV rose to 1,202.6p. Chairman Lord Jacob Rothschild warned back in November that the firm had experienced some of the most torrid markets seen in his lifetime.RIT's investment policy remains mindful of the view that "... the risks ahead are glaring and global," it said in today's company statement.The investment trust also said that internally managed quoted equity now contributed 15.1% of NAV, compared to 11.6% at September 30, 2011. Share of the London listed fund fell 1p to 1,234.00p at 10am local time.