(Bloomberg) -- If you’re a bond manager, you may think index funds are the headache of your stock-picking colleagues.

Think again. U.S. managers tracking indexes oversaw a record 27 % of the money in taxable-bond mutual funds and ETFs as of Feb. 29, compared with 20 % at the end of 2013, according to Morningstar. While the proportion is smaller than the roughly 40 % of equity-fund assets in passive products, the trend and the reasons -- cost savings and a poor performance of active managers on average -- are similar.

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