Most American millionaires are not in Silicon Valley but in law firms and car dealershipsWho Is Really Rich in America? (Hint: Main Street Millionaires)

Two economists dug into US households worth over $5 million and found they hold more than 13 times the wealth of the Forbes 400 — by owning thousands of independent local businesses all over the country.

When people picture rich Americans, they picture Bill Gates, Warren Buffett, hedge fund managers. The wealth of the country is not actually concentrated there.

The money sits on Main Street

Two economists studied households with a net worth above $5 million; the average in their data is $25 million. This group holds more than 13 times the wealth of the Forbes 400.

They call them Main Street millionaires. The money sits in LLCs and S-corps in every state, not in a handful of glamorous zip codes.

What businesses they own

The top five industries are law firm partnerships, investment firms (venture capital and private equity), independent car dealerships, management consulting and oil and gas extraction in states like North Dakota and Pennsylvania.

Crucially, none of these industries is dominated by a single giant. Each has thousands of independently owned firms, and the owner does equally well in Nebraska or New York.

Who are they? Typically older, married, White and male; the median age of the $10-million-plus owners is 62. That is not an accident — building a business to that size takes decades.

Eighty percent have a college degree, and 40 percent hold a postgraduate or professional one. Yet decamillionaires who do not own a business are even more educated. Either a degree or a business will do; if you own the business, the degree matters less.

Few inherited it, most built or bought it

Only about a quarter of these firms were inherited. Some 46 percent were founded by their current owner and 32 percent were bought.

Coming from a wealthy family does raise the odds of founding a firm, but 70 percent of founders come from families outside the top 10 percent of income. A bigger variable is which industry your first job was in — that is how you learn the trade and the network.

Getting past $10 million almost always means owning something, and buying an existing firm is more common than starting from scratch. But do not look only at the winners: only around 5 percent of founders build a firm worth over $5 million within ten years, and half shut down as independent entities within five.

Failure is not ruin — more than half of founders end up doing just as well as their salaried peers. The road takes decades, and there are no shortcuts.