I love long term graphs, this one is from the S&P 500 (USA), the grey areas are recessions.
It is impossible to time the market correctly, but somebody who was roughly right would have made a bomb:
- Buy the US market somewhere between 1980 and 1990
- Sell in 1999/2000
- Buy in 2002/2003
- Sell in 2007
- Buy in 2009
But even people who bought the market in 1980 and just held on to their shares would have done pretty well, they would have made about 15 times their money.