海角大神

The biggest political news this week won鈥檛 be the Democratic convention. It will be Friday鈥檚 unemployment report.

If the trend is good 鈥� if the rate of unemployment drops and the number of payroll jobs is as good if not better than it was in July 鈥� President Obama鈥檚 claim we鈥檙e on the right track gains crucial credibility. But if these numbers are moving in the wrong direction, Romney鈥檚 claim the nation needs a new start may appear more credible.聽

I don鈥檛 recall a time when these jobs numbers, compiled monthly by the Bureau of Labor Statistics (a highly professional group whose findings are completely insulated from politics), were as politically significant as they鈥檒l be this Friday, and the first Fridays in October and November.聽

Yet these numbers are really crude approximations. They鈥檙e adjusted for seasonal variations 鈥� based on historical data that may have less significance today, when the economy is still struggling to emerge from the worst downturn since the Great Depression. The numbers are also subject to corrections and revisions later, as more data come in.聽

But perhaps the biggest flaw 鈥� and irony 鈥� is that when and if jobs really do start to return, many of the people who had been too discouraged to look for work start looking again. And when more people are looking, the rate of unemployment rises 鈥� because that rate is based on the percent of Americans actively looking for work. Those who have stopped looking aren鈥檛 counted.