For any economy, there are two basic factors determining how many jobs are available at any given time. The first is the overall level of activity - with GDP as a rough, if inadequate measure of overall activity - and the second is what share of GDP goes to hiring people into jobs. In terms of our current situation, after the Great Recession hit in full in 2008, US GDP has grown at an anemic average rate of 1.3 percent per year, as opposed to the historic average rate from 1950 until 2007 of 3.3 percent.