It's worse than that, Jim

The problem with (un)employment statistics is that if Microsoft shed 5,000 software engineers in the same month that McD's take on 5,000 burger flippers, there's no net change in employment levels. Economists are human too and are easily tempted to use statistics that are readily available rather than try and delve behind the raw numbers to see what's really going on (cf. the use of GDP - an almost meaningless number, but one that's regularly produced by nearly all governments as part of their tax collection activities).