Danny Crichton, TechCrunch:

The average age of a startup founder is about 41.9 years of age among all startups that hire at least one employee, and among the top 0.1 percent of highest-growth startups, that average age moves up to 45 years old. Those ages are taken from the time of the founding of the company.

And

One interesting dynamic in the data is that older entrepreneurs appear correlated with better startup performance. “For example, the 1,700 founders of the fastest growing new ventures (1 in 1,000) in our universe of U.S. firms had an average age of 45.0 (compared to 43.7 for the top 1% and 42.1 for the top 5%),” the researchers wrote.

Indeed, it’s not just that older entrepreneurs are more successful, but that younger founders are less successful. “Overall, we see that younger founders appear strongly disadvantaged in their tendency to produce the highest-growth companies,” the researchers wrote (italics in original). One reason, they argue, is that older founders tend to have more years of experience in their industries.