Barry Ritzholz at The Big Picture has this chart comparing the current bear market in stocks to previous plunges, 1929 to 2009.

Mike Mandel at Business Week cuts the numbers a different way, painting an even gloomier picture. He notes that the S&P 500 is down 50% adjusted for inflation (February 17, 1999 to February 17, 2009). He calculates that the stock market was down roughly 50%, adjusted for inflation, in the worst ten years of the Great Depression (September 1929 to September 1939).

One last set of numbers: The last quarter century–until recently–was considered the era of private enterprise innovation and poor government fiscal management. From 1983 to 2008, the annual total return on stocks was 9.8% a year. Yet, according to Peter Bernstein, the dean of finance economists, long Treasuries produced an 11% average annual return over the same time period. Go figure.