U.S. junk bonds posted their steepest decline since 2011, intensifying fears that a six-year bull market in stocks and other risky assets is nearing an end. The largest high-yield exchange-traded fund, the $15 billion iShares iBoxx $ High Yield Corporate Bond ETF , dropped 2%, to close at $79.52, its lowest since July 2009. Friday’s trading volume of 53 million shares doubled a record set Tuesday. The retreat punctuated a day of heavy selling across markets, with the Dow Jones Industrial Average tumbling 310 points and U.S.-traded crude dropping 3.1%, to $35.62 a barrel. Oil’s 11% decline was its biggest weekly fall since March. Traders said much of Friday’s decline was triggered by the abrupt closure of a high-profile junk-bond mutual fund. Investors in the Third Avenue Focused Credit Fund learned this week that they won’t get all their cash back for months or more, as Third Avenue Management […]