"Behind the Pay Gap" purports to show that one year after graduation, women are paid 80% of what men earn.

Equal Pay Day has become one of our annual rites of Spring. And once again Hillary and her gal-pals were out in force, trying to convince us that women are undervalued and underpaid in the American workplace.

This year the gender victimologists came armed with a new report from the American Association of University Women, "Behind the Pay Gap," which purports to show that one year after graduation, women are paid 80% of what men earn.

The AAUW’s press release featured this startling statement: “Women earn less even when working in the same career field, likely due to sex discrimination.” So no surprise, media coverage of the study trumpeted the 80% figure like it was revealed truth.

But women who are familiar with the AAUW’s long-standing gender agenda began to question the study.

Mary Kay Ham sardonically wondered why she, as a highly-educated columnist, should be paid less than a dime-a-dozen brain surgeon. Another blogger asked pointedly, “If an employer is only concerned about the bottom line, why would s/he hire a man at all to perform a job where an equally qualified woman will do it for 69% of pay?”

To settle the issue, I decided to download the report and see for myself.

I quickly noticed that the 80% figure is deceptive because it doesn’t take into account differences in work hours, occupational choices, and other key variables.

When you do that, the wage gap shrinks dramatically. As the AAUW report finally admits on page 39: “The regression analysis of earnings one year after graduation for the combined sample of women and men shows a gender pay difference of 5 percent, controlling for educational and occupational choices as well as demographic and personal characteristics.”

But it turns out the AAUW study omitted a number of important factors in its analysis, so even the 5% figure is exaggerated.

For example, many men coming out of high school enter the military and later go to college. These men command a bigger paycheck upon graduation. Likewise, men tend to accept big-city jobs with longer commute times. But the AAUW glossed over those facts.

Of greater concern is how the AAUW shoe-horned the many thousands of jobs into 11 broad occupational categories.

Take the medical profession, which is evenly divided between the sexes, compared to nursing, which is overwhelmingly female. The AAUW lumped all doctors and nurses into the same “medical professions” group. So you guessed it — doctors are paid more than nurses, and that’s discrimination!

And women who major in business administration gravitate to human resources administration, while men often specialize in finance. Employees who manage a corporation’s financial lifeblood tend to be paid well. But the AAUW put both groups into the “business and management” category. Yikes, more discrimination!

This isn’t the first time the American Association of University Women resorted to smoke-and-mirrors research to further its political agenda.

Back in 1992 the AAUW published the report, "How Schools Shortchange Girls." The report purported to show that American schoolgirls were being kept down by the ever-present patriarchy.

But Diane Ravitch, former assistant secretary of education, took issue with that conclusion, saying flatly, “The AAUW report was just completely wrong. What was so bizarre is that it came out right at the time that girls had just overtaken boys in almost every area.”

To redeem itself, the AAUW finally came out with a second report. "Gender Gaps: Where Schools Still Fail Our Children" had to admit – a-ha!– that, “National data indicate that girls consistently earn either equivalent or higher grades than boys in all subjects at all points in their academic careers.”

But that oops-I-goofed document could not reverse the hysteria generated by the first report, which fueled the passage of the Gender Equity in Education Act in 1994, a law that contributes to the boy crisis we’re now seeing.

But memories are short, and no doubt some will be fooled by the AAUW’s gender wage gap tom-foolery.

But beyond the claims of sex discrimination, "Behind the Pay Gap" contains a put-down to all working women. That message reads, Ladies, you are unwilling to accept the financial consequences of your decision to work shorter hours and in less lucrative occupations.

That’s patronizing and insulting to the women who don’t believe they need a government mandate or gender quota to get ahead in life. Hopefully this time around not so many will be taken in by the AAUW’s creative calculations.