Investors poured $347 billion into exchange-traded funds globally during 2015, fund-manager BlackRock Inc. (BLK.N) said on Sunday, setting a new record for the industry. BlackRock said its own haul of $130 billion in new money also set a record in global flows for its iShares ETF business, surpassing the previous annual record set in 2014, when investors added $103 billion in new money to the funds.

ETFs, generally a basket of stocks, bonds or other assets, grew at a record rate despite markets struggling in 2015 to deliver the broad gains they have posted since rebounding from the financial crisis in 2009. Global ETF assets now total about $3 trillion.

In the United States, inflows of $228 billion last year were not enough to top the record $246 billion brought in during 2014, according to the BlackRock data.

A third-party data provider, ETFGI LLP, said its estimates for the year also showed a similar increase in new assets for global ETFs over 2014 and a decrease in U.S. flows.

It was a year of slim returns.

The largest U.S. ETF, SPDR S&P 500 ETF (SPY.P), delivered 1.34 percent in total returns in 2015. The iShares Core U.S. Aggregate Bond ETF (AGG.P) , the largest U.S. bond ETF, eked out 0.48 percent, according to Morningstar Inc (MORN.O).

Investors looked to ETFs tracking stocks in places like Europe and Japan, hoping shares of companies there would be boosted by stimulus from central bankers.

New York-based BlackRock, with more than $1 trillion in global ETF assets, is the largest provider of such funds, as well as the world's largest money manager overall. The funds have benefited, as they offer an alternative to bonds, mutual funds, futures and other financial products.

BlackRock also set new records for growth in the United States, where its $97 billion in 2015 intake topped the $82 billion brought in year prior. In Europe, the company's $34 billion in cash flows were also a record, ahead of the $20 billion collected in 2014.

Vanguard Group Inc. estimated its U.S. ETFs took in $76 billion during the year, also a record, lifting the company to second among ETF providers by total assets in 2015 for the first time.

The two top managers, iShares and Vanguard, account for three-quarters of the new cash brought into the U.S. ETF market, according to Morningstar data. BlackRock is to report its fourth-quarter results on Jan. 15.

(Reporting by Trevor Hunnicutt; Editing by Dan Grebler)