We're coming up on Equal Pay Day again. That's the day in April every year -- this year the 24th -- when women's earnings finally catch up with what men made by Dec. 31 of the previous year. Women's groups, led by the National Committee on Pay Equity, will rally on Capitol Hill to call attention to the issue.

The pay gap is still a stubborn problem, with women who work full time year-round making 76 cents to a man's dollar. Though it consistently polls No. 1 with female voters in election years, politicians don't seem motivated to do much about it.

Some people say pay disparities between women and men are an illusion -- women just like to choose jobs that pay less because they're not as risky or have shorter hours. But the data don't back up these claims. Even when researchers take into account such factors as part-time work or time out of the work force to care for kids, the numbers show that men make more. Another problem that just won't go away is that so-called "men's jobs," like plumbing, pay more than "women's jobs," like nursing. That tells us something about what we value as a society, and it's not women's work.

The Fair Pay Act, a bill that would help narrow the gap, has grown old bouncing around Capitol Hill since the early 1990s, never receiving as much as a hearing. If the FPA ever passed, it would require employers to rate their jobs on skill, effort, responsibility and working conditions, and equalize pay for comparable jobs even if the job titles and duties are different. Employers naturally resist this, citing loss of "competitive advantage," but women's advocates suspect the real reason is that the numbers would be too damning. Women might even get big ideas like suing their employers for sex discrimination in pay and promotion, as female workers at Wal-Mart have done in the largest class-action suit in history.

A new book released this month from The Feminist Press -- "Taking On the Big Boys" by Ellen Bravo, longtime CEO of 9 to 5, an advocacy organization for working women -- attacks the pay equity issue head on. Bravo enlightens the reader in a no-nonsense way on deep-seated workplace attitudes and practices that hinder women's progress on the pay front. More importantly, she shows us how public policy is influenced through a variety of tactics used by opponents. One such tactic is catastrophizing, meaning predicting the downfall of capitalism as we know it if women catch up with men in earnings. Poster boy for this tactic is Chief Justice John Roberts, who dismissed the concept in the FPA as a "pernicious" redistribution of wealth, saying, "Their slogan may as well be 'From each according to his ability, to each according to her gender.'" Pretty scary stuff for the women of Wal-Mart, should their case, now on appeal, reach the Supremes.

"Taking On the Big Boys" shows us how continued monitoring and enforcement will be necessary, even for companies that want to do better. The FPA also contains a provision that would require companies to report earnings by race and gender in each job category -- not anybody's salary on a bulletin board, but just overall statistics, so women could see how they were faring compared to the guys in the company overall.

While there's no law now that says companies have to disclose how they pay and promote their workers, there's no law that says they can't. Wal-Mart agreed last year under stockholder pressure to post its EEO-1 form online, showing broad job categories by race and gender (the form does not include pay data). Some disclosure is better than none, but all companies should go a step further and release pay data for women and men by job category, as Ben & Jerry's has done for years. If pay scales are equitable, there should be nothing to hide. Women could see right up front if the company is fair. It would eliminate the need for lawsuits and create tremendous employee loyalty and customer good will. That ought to be worth 24 extra cents in the pay envelope

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