Mark Zuckerberg -- clearly no stranger to startup success -- said "young people are just smarter." Maybe that's true.

But that doesn't mean younger entrepreneurs are likely to be more successful than, um, more "seasoned" entrepreneurs. A study conducted by the Census Bureau and two MIT professors found the most successful entrepreneurs tend to be middle-aged -- even in the tech sector.

After compiling a list of nearly three million company founders who hired at least one employee, the researchers found that the average startup founder was 45 years old when they founded the most successful tech companies. (In general terms, a 50-year-old entrepreneur is almost twice as likely to start an extremely successful company as a 30-year-old.)

Another study published in Journal of Business Venturing found that entrepreneurial success, where age is concerned, is fairly U-shaped. (Especially for female entrepreneurs.)

Granted, younger entrepreneurs may have better insights into how new technologies could meet consumer wants and needs. And younger entrepreneurs may be less risk averse; it's harder to quit a full-time job and take a flyer on a startup if you have a number of mouths to feed.

But on the flip side, older entrepreneurs can benefit from their broader business, leadership, and execution skills and experience. Inexperience makes developing sound strategies more difficult. Inexperience makes building a team more difficult. Inexperience makes turning an idea into a reality -- much less a profitable reality -- much more difficult.

As the researchers write, "Age has ... a positive effect on subjective success, firm size, and financial success."

Because the only way to decrease the number of things you don't know -- and, just as important, have a good grasp on which things you do well, and which you don't -- is through gaining experience.

If you're in your 40s, and want to start a business, don't let age hold you back.  If you're in your 50s, don't let your age hold you back. If you're in your 60s, don't let age hold you back.

The skills, experience, and savvy you've acquired could mean you're the perfect age to start a business.