The 2012 edition of Bloomberg BNA’s Union Membership and Earnings Data Book has been published, and it has the latest breakdowns of U.S. Census data on union density rates—the percentage of a state or city’s wage-and-salary workforce, age 16 and over, who are members of labor unions.

Of the 50 states (and the District of Columbia), New York reported the highest union density in 2011. That’s no small feat, considering that New York also has the third-largest workforce in the country. Almost one-quarter (24.1 percent) of New York’s approximately 8 million workers are union members. 

Only California can claim more union members, but due to the even larger size of its workforce—nearly 14 million—it ranks just eighth on the union density list, with 17.1 percent. Texas also has more workers than New York, but it has a relatively tiny union contingent. Only 5.2 percent of the right-to-work state’s 10 million-plus workers belong to a union, placing it 41^st in union density.

The top five states in union density in 2011 were:

1. New York (24.1 percent)

2. Alaska (22.1 percent)

3. Hawaii (21.5 percent)

4. Washington (18.9 percent)

5. Michigan (17.5 percent)

 The bottom five states in union density were:

51. North Carolina (2.9 percent)

50. South Carolina (3.4 percent)

49. Georgia (4.0 percent)

48. Arkansas (4.2 percent)

47. Louisiana (4.4 percent)

All five of these states have right-to-work laws, which prohibit union security agreements that make union membership or dues payments compulsory. In fact, of the 20 lowest-density states, only one—New Mexico, at number 35—is not a right-to-work state. Meanwhile, 14^th-ranked Nevada is the only one of the nation’s 23 right-to-work states to place in the top 20 in union density in 2011.

Note: I included both public- and private-sector workers in these rankings. However, the Data Book includes figures for just private-sector workers as well.

Additional information about the Union Membership and Earnings Data Book is available here.