Even through the supposedly dull summer months, exchange-traded funds (ETFs) are adding new money at a staggering rate, ensuring that previous years' asset records will fall in 2017, and they will likely do so well before the end of the year. Buoyed by massive inflows to fixed income and ex-U.S. equity funds, assets under management for U.S.-listed exchange-traded products (ETPs), which include ETFs and exchange-traded notes (ETNs), swelled to a record $2.973 trillion at the end of the first half of 2017.

"ETFs and ETPs listed in the United States gathered a record level of $46.58 billion net inflows in June," according to ETFGI, a London-based ETF research firm. "This was the 16th consecutive month of positive net new asset flows. Year to date, net inflows stand at a record level of $247.39 billion, which is significantly above the $66.3 billion of net new assets gathered at this point last year." (See also: 2017 ETF Inflows Are Staggering.)

The good times for ETFs did not end when June wrapped up. U.S.-listed ETFs now have over $3 trillion in a combined assets after $23.4 billion flowed into ETFs and ETNs in July. "To give you an idea of how strong the flows have been, last year ETFs had record inflows of $287 billion the entire year. We're at $272 billion in inflows in just the first seven months," reports CNBC. "Put another way: the inflows in the first seven months have equaled about 9 percent of all the ETF assets under management. That is a lot of money coming in."

On a year-to-date basis, the iShares Core S&P 500 ETF (IVV) is the top asset-gathering ETF with over $21 billion in new assets added. Including IVV, four ETFs have added more than $11 billion in new assets this year, with the iShares iBoxx $ Investment Grade Corporate Bond ETF (LQD) and the iShares MSCI EAFE ETF (EFA) in position to top $10 billion in assets added in a matter of days or weeks. (See also: Fixed Income, International ETFs Lead First-Half Flows.)

Five of the top 10 asset-gathering ETFs on a year-to-date basis are international equity funds, including two emerging markets ETFs. The iShares Core MSCI EAFE ETF (IEFA) is the top asset gatherer among international ETFs with nearly $14 billion in 2017 inflows. Two issuers – iShares and Vanguard – dominate the top 10 ETFs for 2017 inflows. Of those 10 ETFs, six are iShares funds, while the other four are Vanguard products. (See also: Another Assets Record for US ETFs.)

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