That data is almost 20 years old now. I don't know how much it has changed since then, though. It also only deals with 'private sector' labor, whereas the OP specifically mentioned state employees in the pool of 'labor'.

EDIT: Wait... The chart title says 1979-2013, which is what the chart says... but the source citation says it came from 1979-1998... which is why I thought it was 20 years old... not sure where they got the rest of the data from.