2012 was a banner year for ETF buying as $191 billion flowed in to top the previous record from 2008, according to Morningstar.

After two years of trailing Vanguard, BlackRock’s (NYSE: BLK) iShares took back the ETF flows crown with nearly $61 billion in 2012 flows, the investment researcher added.

However, SPDR S&P 500 ETF brought in more new cash than any other ETF, with $20 billion in flows, most of which came in December. “Due its hyper-liquidity and the ability to trade SPY at low costs, traders tend to use it to rapidly place market bets, so flows into SPY are a good barometer of market sentiment,” Rawson wrote.

In 2011, the S&P 500 briefly lost its title as the largest ETF to SPDR Gold Shares (NYSEArca: GLD), which is also managed by State Street (NYSE: BLK), when gold prices surged to all-time highs. GLD, the gold ETF, currently holds about $71 billion in assets. [Can Gold Fund Reclaim Title of World’s Largest ETF?]