FYI: As far as funds go, including exchange-traded funds, there is over $2 trillion following the S&P 500. The world’s largest exchange-traded fund is an S&P 500 ETF: The SPDR S&P 500 ETF (SPY[2]). In the U.S., SPY, the Vanguard S&P 500 ETF (VOO[3]) and the iShares Core S&P 500 ETF (IVV[4]) are three of the largest ETFs of any stripe.
However, as is often the case with ETFs, size is not a guarantee of success. Sure, S&P 500 ETFs are inexpensive, highly liquid and easy to comprehend. Those are all positive traits to be sure, but those traits do not ensure success for S&P 500 ETFs.
The good news for investors is that there are myriad alternatives to S&P 500 ETFs, including scores of so-called core and total-market funds.
Regards,
Ted
http://investorplace.com/2015/12/etf-alternatives-sp-500/print