One important measure of labor vitality is the share of the working-age population that is employed. In January, that share was near a three-decade low of 58.4%, compared with about 63% in 2007. That means about 7 million fewer people 16 years and older have jobs today than at the end of 2007.
"The significance of that is, in contemporary America, most of the households have multiple earners," O'Keefe said. "Their spending patterns -- car loans and mortgages -- are predicated on multiple incomes, not primary breadwinners."