Entrepreneur surveyed 500 small business owners across the country to ask how they're feeling about their business.

Here's what we heard: 61% said they're feeling stressed — and 56% of those stressed-out owners said they're losing sleep because of it.

How much less? The average was 7 hours — though 20% of the group said it was only 3 to 4 hours per week. Millennials owners are losing the most sleep, at an average of 7.5 hours a week, and men are losing slightly more sleep than women (7.3 hours versus 6.9 hours).

Related: Do You Get More Sleep Than Elon Musk, Jeff Bezos and Winston Churchill?

In a word — money.

Nearly half of respondents (47%) said they've........

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