Here’s a list most people would die to be on: The Forbes 400. This year’s list of the wealthiest Americans has an aggregate net worth of $2.29 trillion, which is up almost $300 billion from just a year ago. Many of the faces are familiar: Bill Gates, Warren Buffett, the Waltons, Charles & David Koch, and of course Oprah.

However, there are a few new faces including one of the youngest, a self-made billionaire who dropped out of college and bootstrapped her way to success at what appears to be a meteoric pace.

Of the women on this list, who have more than the GDP of nations around the world, many inherited their wealth or married well, such as Alice and Christy Walton (Walmart), Lauren Powell Jobs (Apple), and Jacqueline Mars (Mars candy).

Then there are the self-made billionaires whose sweat and smarts have helped them build some of the world’s biggest brands and companies. In the words of rapper Drake, they “started at the bottom, now [they’re] here.”

At 60, Oprah’s media empire built her a $3 billion fortune. Meg Whitman, CEO of Hewlett-Packard, who made her money at eBay, is worth $2 billion. Little-known Diane Hendricks with $3.6 billion in net worth is founder and chairman of ABC Supply.

The most surprising is Elizabeth Holmes, who at just 30 years of age, has a net worth of $4.5 billion. Her route to riches began with studying chemical engineering and then dropping out of college to found a blood testing company.

Forbes reports:

Each year, Forbes crunches the net worth of every American billionaire to see who will make the exclusive Forbes 400 list. But 11 members of this club are luckier than the rest: they are in good health, have full heads of hair and many, many years to spend their fortunes.

A close third is newcomer Elizabeth Holmes, also 30 but born in February, who joins the ranking this year thanks to her blood testing company Theranos. Holmes founded the Palo Alto, Calif.-based company with money saved for college, and has reportedly raised more than $400 million, valuing the 10-year-old company at $9 billion.

The Business Insider provides a snapshot of Elizabeth Holmes' story:

The next time you get a blood test, you might not have to go to the doctor and watch vials of blood fill up as the precious fluid is drawn from your arm.

Instead you might be able to walk into a Walgreens pharmacy for a reportedly painless finger prick that will draw just a tiny drop of blood, thanks to Elizabeth Holmes, 30, the youngest woman and third-youngest billionaire on Forbes' newly released annual ranking of the 400 richest Americans.

Holmes dropped out of Stanford at 19 to found what would become Theranos after deciding that her tuition money could be better put to use by transforming healthcare.

Holmes recognized that process was ripe for disruption.

It took a decade for her idea to be ready for primetime, but now it seems that her decision to drop out was undoubtedly a good call. Last year, Walgreen Co. announced that it would be installing Theranos Wellness Centers in pharmacies across the country, with locations already up and running in Phoenix and Palo Alto, California. And Holmes has raised $400 million in venture capital for Theranos, which is now valued at $9 billion (Holmes owns 50%).

These women are inspiring and accomplished. Even more, they remind us that the American is still a land of opportunity contrary to what naysayers will have us to believe.

Free markets and freedom make room for one person with an idea to take it to market and create measureable value for society. In the case of Elizabeth Holmes, her foray into blood testing is saving lives by making the process more efficient, cheaper, and less scary for those who need their blood tested.

Economic freedom has been on the decline over the past decade as greater government involvement and regulation of the private sector raises costs of starting and doing business. The barriers to entry are so high for entrepreneurs, that unless you have tenacity and access to capital, it may be difficult if not impossible to overcome.

If we want to see more entrepreneurs like Mark Zuckerberg or Elizabeth Holmes, our government should scale back regulation and promote policies that make market entry and foster competition easier.