From the abstract:
On January 23, the Bureau of Labor Statistics (BLS) released its estimates for union membership in the United States in 2012. This issue brief focuses on the union membership numbers by state. In addition to presenting the BLS estimates for overall union membership in each state, we also provide our own breakdown of state union membership in the private and public sector.
Figure 1: Change in Union Membership, 2011-2012, All Workers
Figure 2: Change in Union Membership. 2011-2012, Private Sector
Figure 3: Change in Union Membership, 2011-2012, Public Sector