Nearly half of all flows into U.S.-listed exchange-traded funds this year has gone to four low-cost funds from BlackRock. The iShares Core MSCI EAFE ETF tops the list, having taken in $13.7 billion since Jan. 1, according to data compiled by Bloomberg. Not far behind is the iShares Core S&P 500 ETF, which has swelled by $12.2 billion. The iShares Core MSCI Emerging Markets ETF and the iShares Core U.S. Aggregate Bond ETF also make the cut, taking in $5.1 billion and $2.4 billion respectively, the data show. Read the original story from Bloomberg.