Investors allocated $73.5 billion to U.S.-listed exchange-traded funds in the first half, according to a report by ETF.com.
Approximately two-thirds of that amount poured into equities, amid optimism about U.S. economic recovery.
The report said total ETF assets listed in the U.S. at the end of June stood at $1.9 trillion, nearly 7% higher than at the end of 2013 and 26% higher than the year-earlier period.
The asset growth reflected a nearly 6% increase in the S&P 500 index.
The report noted that this year's asset gathering has so far lagged the pace needed to match the one-year inflow record of $189 billion set last year.
Still, that was not out of the question, as inflows appeared to be accelerating. In June, they topped $25 billion, according to the report.
ETF.com's data showed that the top gainers in the first half were the following:
1. Vanguard: Vanguard FTSE Developed Markets (VEA)—$3.9 billion
2. Vanguard: Vanguard REIT (VNQ)—$3.4 billion
3. State Street Global Advisors: Energy Select SPDR (XLE)—$3.3 billion
4. Vanguard: Vanguard S&P 500 (VOO)—$3.3 billion
5. Vanguard: Vanguard FTSE Europe (VGK)—$3.2 billion
6. Vanguard: Vanguard Total Stock Market (VTI)—$2.9 billion
7. BlackRock: iShares MSCI EMU (EZU)—$2.7 billion
8. BlackRock: iShares 7–10 Year Treasury Bond (IEF)—$2.5 billion
9. Vanguard: Vanguard Total Bond Market (BND)—$2.3 billion
10. BlackRock: iShares MSCI EAFE (EFA)—$2 billion
