VC firm First Round Capital turns 10 this year. You may not have heard of them before--but you've heard of the companies they back, like Birchbox, Blue Apron, Square, Uber, Upstart and Warby Parker.

"Venture capitalists are constantly telling the entrepreneurs they invest in to make data-driven decisions. But as an industry, we haven't been very good at doing it ourselves," begins their provocative 10 year anniversary report, just released. What have they discovered in a decade of investing in early stage companies?

"We evaluated every company's performance by looking at how much their value has grown, or shrunk, between our initial investment and their fair market value today, or at exit," according to partner Josh Kopelman.

Some of the correlations they found in the data run counter to deeply held beliefs in the venture capital industry.

1. Female founders outperform male peers 63%.

First Round found this correlation between performance and having a female founder or co-founder to be the number one result of their number crunching.

"Our investments in companies with at least one female founder were meaningfully outperforming our investments in all-male teams. Indeed, companies with a female founder performed 63% better than our investments with all-male founding teams." They know what they are talking about--their startups include True, a bra fitting application; Ringly, a wearable jewelry concept; Keep, a home design platform; DogVacay pet sitting; Cloe & Isabel social commerce jewelry; CareDox for parents and schools . . . you're getting the idea. They really know what female founders are producing and they are investing early--and often.

2. Silicon Valley has no strangle-hold on financial success.

In fact, the First Round data says companies outside of Silicon Valley and New York perform 1.3% better.

3. Personal relationships aren't predictors.

First Round carefully tracked how it met its founders over the 10 year period--we're talking 600 founders they've invested in across 300 investments. They learned that startups they discovered through "social proofs"--like demo days, events, social media, and the startup's own marketing-performed 58% better financially. Even founders who just cold called them--instead of being referred--did better than those who were introduced.

There are seven more surprising correlations between founders and performance in the full report, which is available here.