Since the Mackinac Center’s founding, the fight to neuter unions has been on. We’ve seen it in the newspapers, on TV, in the mailbox, in emails, and online in every available form: Facebook, Twitter and YouTube. “Save some money: quit the union.”

Only it doesn’t work that way. Even after 28 years, it still pays to be a member.

One of the vast number of data points followed by the U.S. Bureau of Labor Statistics are wages and salaries of the “Educational Services” industry. By that, they mean people who work for K12 schools, colleges, trade schools, public as well as private. This category encompasses jobs of every kind.

BLS presents this data in a multitude of forms, and it can reform it along any number of variables or cross tabs: gender, geography, age, on and on. One of these is union status.

The advantage to union membership is obvious, even after years of attacks. When you have numbers, you have leverage. You can affect change in your school, for your kids and in your wallet. This advantage is even clearer if you go back a few years:

What’s clearer still is why the Mackinac Center wants you to quit: you cost too much. You can be replaced, for a year or two anyway, with a new graduate, until he or she gets tired of the long hours, low pay, abuse and lack of respect and finds another line of work.