First, here's the graph he tracks down, which seems to indicate that stock prices and unemployment have held hands this recession.
My first thought was: Well, maybe improved information technology made employers more sensitive to this downturn. So I went to the Bureau of Labor Statistics to check out unemployment trends, and here's the unemployment graph over the last three decades:
You can see the four big unemployment spikes are: after 74, after 82, after 91, and after 2001. But what happens when you compare unemployment spikes to corresponding stock market troughs? Does Salmon's theory hold that unemployment spikes mark the the beginning of long-term stock rallies? Let's see.
1974
In the recession that began in 1974, unemployment figures peaked in early 1975, a few months after the stock market bottomed out in December, 1974. Conclusion: Unemployment peak was a lagging, but not too lagging, indicator of long-term stock rally.

1982
In
the recession that defined Reagan's first year-plus, unemployment
peaked in the last quarter of 1982. Similarly the stock market saw the
bottom in August 1982. Conclusion: Once again, the peak of unemployment
occurred a few months after the bottom of the stock market.1991
In the recession that swept Clinton into office, unemployment's ceiling occurred during the campaign in the summer of 1992, more than a year and a half after the stock market began to climb from its October 1990 bottom. Conclusion: Unemployment really lagged stock growth in the early 1990s.
2001
In the
recession that followed Clinton's exit and 9/11, unemployment topped in
the middle of 2003, while the the market began its consistent upward
tick in March. Conclusion: Again, a few months after the market began
its steady climb, unemployment peaked.
This article available online at:
http://www.theatlantic.com/business/archive/2009/05/does-unemployment-guide-the-stock-market/18306/
