Not many topics excite startup founders more than the prospect of joining the ranks of Uber and launching a truly disruptive product. The dream is about becoming a unicorn, a company privately backed with VC funds and valued at $1 billion or more.

A new study from Play Bigger provides the evidence: As valued by market capitalization, the amount of these ‘unicorn’ companies are growing faster in the last few years. While a market bubble may be at play, fundamental forces, augmented by new media, may be at the heart of the growth.

“Products and services get discovered and adopted at a speed never seen before,” said Al Ramadan, Play Bigger, a San Francisco-based consulting group. “Word of mouth today—through Facebook, Twitter, Tumblr, Pinterest, and so on—is just so fast, and it is the most effective means of marketing.”

The study looked at companies with a 1 billion dollar valuation before an IPO and determined if that was the best move. What the researchers found is start-ups of today are growing twice as fast of those from a decade ago.

By looking at the market capitalizations of 1,125 firms that started in 2000 or later and divided the number of years since their founding, the researchers were able to map and test their hypotheses of where the “amount raised prior to an IPO predicted growth in market cap after IPO-a proxy for long-term value creation.”

By looking at a sample of 69 companies, the researchers found no correlation between the money raised before their IPO and their long-term success.

“Candidly, we did not expect this result,” says Christopher Lochhead, Play Bigger founding partner. “There’s a lot of belief in Silicon Valley that the amount raised really matters.”

The researchers found two factor that determines long-term success after an IPO.

The first factor is the timing of the IPO. “Companies that go public between the ages of six and ten years generate 95% of all value created post-IPO,” Ramadan says.

While it is hard to interpret the findings, there is one possible reason for this “window.” Many companies are missing their chance for success by staying private too long.

Traditionally, start-ups have taken advantage of private capital from hedge and mutual funds and corporate VC firms. As a result, companies are growing bigger and starting to stay private longer.

If these companies stay private while they experience growth, they may miss their chance for a successful IPO.

The second factor is the company niche. According to the researchers at Play Bill, the majority of post-IPO value creation comes from “category kings.” By carving out entirely new niches, these companies, such as Facebook, LinkedIn, Tableau, and more, capture 76% of the market.

These companies are articulating new problems that can’t be solved by existing products and services and creating new ecosystems to develop to a solution.  

In conclusion, the path forward past an $1 billion valuation can be the challenge. Raising money does not guarantee success.