The media defines a unicorn is any company that surpasses $1 billion in value, and the booming fintech sector is now chock-full of them. Surprisingly, despite their successes and sky-high valuations, most people haven’t heard of these companies. That’s because they are still very new and have a lot of work to do before they catch the big banks. That’s why we created a new viz showing you the ten most valuable fintech companies that remain privately held.

Our list comes from Forbes, which uses valuations from Pitchbook and CB Insights based on the last round of known venture financing. The graphic ranks in order the most valuable fintech companies—the larger the bubble, the more valuable the company. We also included the year in which each company started together with the latest valuation and the company’s logo. That makes it easy to see how one compares to another at a glance.

It’s worth pausing for a moment to understand how venture capital works. When a company needs a lot of money to start a new project of roll out a different product, they often tap the equity market. Think about it like this: the company’s owner sells a small percentage of the company for an infusion of capital. In exchange, the investor gets a share of the profits going forward. Both sides are armed with lawyers and accountants who do this kind of thing for a living, and whatever number they agree to can be extrapolated to an overall value for the company (all things being equal). If I invest $100,000 in exchange for 10% of your company, then the whole thing is worth $1 million. Pretty simple.

That being said, there’s a lot that you can learn by breaking down valuations like our viz. Most obviously, there are several fintech companies valued at over $1 billion, and almost all of them are relatively new organizations. The oldest company on our list, AvidXchange, was created in 2000. The majority were created within the last ten years, with three companies starting in 2013. Simply put, it doesn’t take a lot of time to achieve a phenomenal valuation in this industry.

There’s another hidden story behind our viz. As high as these valuations are—and despite how quickly the companies achieved them—they really aren’t that big. Sure, $10 billion is a lot of money, but that’s roughly the equivalent of the GDP for the Bahamas. For the sake of comparison, Wells Fargo has a market cap well north of $260 billion. Perhaps for these companies to truly experience rapid growth, they have to move away from venture capital and trade on the open markets.

All of this isn’t to deny that fintech is a hot sector with a lot to offer the economy in terms of long term growth. Any company that can keep overhead costs under control while delivering value to underserved (and wealthy) markets will do well.