the percentage of males and female salary?

Meaningless. Try restating the question.

The salary gap is primarily explained by the fact that female engineers, on average, are less experienced than males.

at what, peeing standing up?

surely if the both have engineering degrees, and why would you hire an engineer who didn't, they're equally qualified

by the by, the original question, to me anyway, was about the percentage difference in earnings, not the reason why

Experience has nothing to do with a degree, it has to do with the number of years you have been doing something. Twenty years ago there were even fewer women doing engineering than there are today. Thus, on average there are fewer women with twenty years of experience than there are today. So to say that female engineers are less experienced is absolutely correct.

Now does this explain the difference in salary? It seems to me that you could compare male recent college graduates with female recent graduates (I expect in engineering the salaries would be pretty much the same).

But engineers with 20 years of experience earn more than engineers right out of college. If you are looking at total average salary without taking experience into account, then it makes perfect sense that the male average salary will be higher (since on average males have been in the field for a longer time).

On average, female engineers have been in the engineering field (i.e. are less experienced) then male engineers.

not caring much about the field of engineering, but having worked(1989-97) in a company with engineers (automotive) i much preferred the two female engineers to the 5 male

the one was hilarious, she'd give tours of the plant and when standing on a bridge that crossed the production line, she'd stop to show the process and if there was a particular guy (really shy religious fellow) working the line, she'd put one leg up on the railing so when the guy looked down the line, he'd be looking right up her skirt

during a meeting to establish company guidelines, she told one of the girls representing the workers, that she didn't think that 12 sick days off a year (one a month for period problems) was the solution, the solution was "to bring the bitch in and spread it around", something she was great at