You're missing the point. It's not possible to 'time the market'. If you, or anyone else could, they would be Trillionaires. By picking an arbitrary point in

You're missing the point. It's not possible to 'time the market'. If you, or anyone else could, they would be Trillionaires. By picking an arbitrary point in time - and comparing it to another arbitrary point in time (say, 'today'), you create a straw-man argument. "Even if you miraculously had horrible luck and bought into an index at literally the worst possible time, you would have still made money." Yes, stocks went from some low point, to a higher point today. When you say 'this holds true for every index' - well, a broad ranges of indexes roughly encompasses the entire market. Ergo - you're really just investing in the stock market, not indexes. Unless you know something very specific about VFINX - and have research that other people do not have on the constituent companies, then you are just throwing darts at a wall. If you made money, great, if not, then it's the same thing. What someone who doesn't have specific information is doing when they play the market willy nilly, is simply riding the overall market. And like other asset classes, it goes up and down. There are historical averages for markets, and in the long run you can expect to earn just a little under that. Interest rates are at an historic low, and we have bubble-like conditions in the market - if the Fed increases by a couple of basis points, much of that gain will go away.