Relayed by Citizen Harrison of Minyanville:
13 recessions since 1929 lasted on average 10 months.
Longest - Great Depression, 44 months.
2nd longest - 1973-1975, 1981-1982, each lasted 16 months.
In 13 recessions median S&P bottom occurred 58% of the way through the recession.
Average return from each recession's closing low to the end of the recession was 20.3% while the average return for the year following was 15.9%.
If this recession started in the 4th quarter of 2007 and lasts as long as the Great Depression the bottom (58%) is the 1st quarter of 2010.
(And if it started 4Q2007 it is already the longest recession since the Great Depression even if last week was the low - AM)