It's worth pointing out that index funds can be overvalued and undervalued. For example, the S&P, up until recently, had been overvalued for a long time. The a

It's worth pointing out that index funds can be overvalued and undervalued. For example, the S&P, up until recently, had been overvalued for a long time. The advantage, though, is that whereas it takes days to figure out whether a stock is overvalued, it takes minutes to do the same for a broad-market stock index. Just look at price:long term earnings ratio. In general, under 15 is a probable buy, over 20 means sell if there are better priced assets out there. And don't put all your eggs in one asset class.