A recent survey performed by PayScale has confirmed what's widely been known for a long time, but nonetheless is striking when looking at actual numbers: the tech industry is largely male, and very young.

The Seattle based company surveyed 32 companies to look at the median age of their workers. Only six companies had a median age of over 35, compared to a national average of 42.3 years old for American workers, according to the Bureau of Labor Statistics.

Older companies tend to have an older workforce, which the New York Times attributes to a number of employees who stay with the same company for a long time. Conversely, younger companies often have employees who have been with their company for a shorter period of time, and are therefore more likely to be younger.

Oldest Median Age Youngest Median Age
Hewlett Packard 41 Epic Games 26
I.B.M. Global Services 38 Facebook 28
Oracle 38 Zynga 28
Dell 37 Google 29
Nokia 36 Blizzard Entertainment 30
Sony 36 InfoSys 30
Cisco 35 Monster.com 30

There are other reasons beyond company age that contribute to age medians, says Katie Bardaro, lead economist at PayScale. "The firms that are growing or innovating around new areas tend to have younger workers. Older companies that aren't changing with the times get older workers."

This can in part be attributed to the skillsets of employees. For example, older workers tend to know C# and SQL, according to Bardaro, but younger generations learn newer languages and technologies like Python and Hadoop.

In addition to the younger workforce, the tech industry is also stacked with men. The survey had 21,700 respondents, and only around 30 percent were female.