A report about a gender gap in Los Angeles city employees’ pay doesn’t mean what some readers apparently took it to mean, but it still says something important to know about the roles of women in the workforce.

That’s worth clarifying after the report released by City Controller Ron Galperin was ridiculed in a couple of letters to the editor published in the Daily News.

Galperin’s data showed that women on the L.A. city payroll earn 83 cents for every $1 paid to men.

In response, letter-writer Bill Costello of La Crescenta said the study is “the most idiotic example of comparing apples to oranges I’ve ever heard of,” and Jim Ridosh of Northridge called the newspaper’s article about it is “misleading and an affront to honest journalism.”

The letter-writers’ complaint: Galperin’s data compares the average salaries of all women and all men on the city payroll, instead of comparing the salaries of women and men doing the exact same jobs. Thus, the figures fail to show that women are being shortchanged on payday.

Frankly, the letter-writers miss the point. There’s no need to study if women are getting less for the same work and seniority; they aren’t. City employees’ salaries are dictated by law and union agreements; a woman and man who started the same job on the same day would be paid the same.

The report and news stories about it don’t say — don’t even imply — that sort of gender gap.

What they do show is the difference in the kinds of jobs women tend to do. Mainly lower-paying jobs.

Examples: The category of city workers with the highest percentage of women, “administrative support,” pays them 28 percent less on average than the category with the lowest percentage of women, “skilled craft.” The city department with the highest percentage of women, the libraries, pays them 33 percent less on average than the department with the lowest percentage of women, the fire department.

You can see the data on the controller’s website (charts are here and here).

As Lowell Goodman, spokesman for the controller’s office, said when I called to ask about the particulars of the report, “people can draw their own conclusions.”

Much of what it shows hews to stereotypes — women are librarians, men are firefighters. But some may challenge stereotypes — for instance, 70 percent of city accountants are women.

It also shows that by making 83 percent of what men make, women employed by L.A. city are doing better than women nationally (77 percent, using the same study methodology as Galperin’s) but not as well as all women working in L.A. (92 percent).

Whether discrimination is a factor in the gender gap is a question for other studies. No, this one doesn’t show the most glaring form of discrimination, women making less for equal work. But it still offers a valuable snapshot of L.A.’s working world.