The Bureau of Labor Statistics is out with its figures on union membership in 2014. Overall membership, aka density, fell to 11.1% of the workforce, from 11.3% in 2013. The decline was more than entirely the result of slippage in the private sector, down from 6.7% to 6.6%.

Public sector density, perhaps surprisingly, rose, from 35.3% to 35.7%. Since private sector employment is more than five times that of the public sector, the private sector decline dominated the public sector’s rise, producing the overall drop.

Here’s a graph of union density over time. Current private sector density is half what it was in 1930, just before the great surge in membership during the Great Depression. Its rate of decline has slowed over the last decade, but there’s no sign of a turnaround. And despite the uptick in public sector density last year, the line has been essentially flat for thirty years.