Here's an oldie but a goodie: Dow 10,000.
We last saw that level (on the way up, that is) six years ago, and we first crossed Dow 10,000 a full 10 years ago. (The latter fact is no doubt deeply depressing to buy-and-hold investors, but at least it has a nice symmetry to it.)
Dow 10,000? Slam dunk. Dow 11,000? Not so much. -- DailyFinance
It's interesting to observe the chart: Dow first reaches 10,000 level 10 years ago. The biggest bull run is between Oct 9, 2002 and Oct 9, 2007. Also you will, depressingly, observe that had you put your money in the Dow in 1999 when it first reached 10,000 and did not sell, you would get your money back now after quite a ride!