How does a chart allow one to trace the cause of income inequality?
Do you know many union employees? Ask the ones who haven't been there for a long time what they think of the union. Their answers might surprise you.
Do you realize that the sorry state of education in the US is partially due to teachers' unions? Are you aware that bad teachers in public school cannot be fired if they have tenure, unless they do something really horrendous?
Do you think that companies hampered by high salaries and benefits for manual labor employees can compete in the global market, or even in the domestic market where non-union alternatives exist?
I guess some people here are still under the delusion that unions help the average worker, while those who oppose unions are heartless corporate apologists.