In recent weeks, Pacific Investment Management Co founder Bill Gross says he has "lost sleep" over an ill-timed bet on Treasuries.

During an interview at Pimco's Newport Beach, California headquarters, Gross, manager of Pimco's Total Return Fund, the world's biggest bond fund, acknowledged that his decision to sell all of the fund's Treasury holdings in February, and then use derivatives to place wagers against government-related bonds in March, was a "mistake".