With apologies to David Letterman, here are the top 10 reasons to believe that the recession is over -- including the one reason you might not believe it's over. And a reminder that even if the recession is officially over -- which won't be declared until hindsight -- you might not feel it personally for quite a few months.

10. The recession is over because it's time for the recession to be over.

The average recession since 1940 lasted 10.1 months. The two previous longest recessions since the Great Depression were the 1973-74 recession, which lasted 16 months, and the 1881-82 recession, which also lasted 16 months. The current recession officially started in December 2007 and thus has now lasted 19 or 20 months. Enough already.

(Yes, it's possible for recessions to last longer. The Depression that started in 1929 officially lasted 43 months, before moving out of negative territory, but the economy fell back into a 13-month recession in 1937.)

9. The recession is over because consumers have started saving again.

Every month since June 2005 until recently, the savings rates has been negative or zero. In other words, consumers had been financing their lifestyles on their credit cards. But consumers started saving last fall, and the savings rate has now surged to 6.9 percent, a 15-year high as of July.

8. The recession is over because the housing market has started to rebound.

Sales of new single-family homes rose 11 percent in June, the largest monthly increase in more than eight years, while the inventory of unsold new homes fell to the lowest level in more than a decade. And sales of existing homes rose for the third consecutive month. Median home prices continued to fall for the 13th straight month, albeit at a slower rate than previous months, according to the Standard & Poor's/Case-Shiller index.

7. The recession is over because CEOs are more confident.

You might not be too impressed with corporate performance, but at least chief executives are becoming more optimistic. The Conference Board polls CEOs quarterly on their outlook. The most recent survey shows almost 55 percent of CEOs now expect economic conditions to improve in the next six months -- up from 17 percent last quarter. This is the second-largest increase in the survey's 23 years -- surpassed only by the jump out of the 2001 recession. (Thanks to Jim Stack of InvestechResearch for highlighting this indicator.)

6. The recession is over because the Leading Indicators are saying so.

The Conference Board Leading Economic Index increased for the third consecutive month, rising 0.7 percent in June. The six-month change in the index has risen to 2 percent -- up from a decline of 3.1 percent in the preceding six months.