Congratulations, you’re officially a member of the 10-digit club. You created an amazing company with millions of customers and reaped the rewards in cold hard cash. You made it. You’re a billionaire today! But if you’re still a billionaire tomorrow, shame on you.

I’m not here to tell you how to spend your money. Do what you want. But it’s important that you know what being a member of the .00001 percent really means. Let’s start with some math. If you earn 1% interest on your billion, you’ll make $10 million a year by doing nothing. If you get 5% on your money, it’s $50 million a year. 10%? $100 million a year. $274,000 a day!

Now, pretend you’re Jeff Bezos. You have at least $100 billion. You earn anywhere from $1 billion to $10 billion a year on your money. That’s upwards of $27 million a day! A DAY! So, what are you going to do?

Sure, you could build a colony on Mars, or buy a fleet of yachts, put your name on a thousand buildings, or even try to stop malaria. Those are big things. But have you thought about doing small things?

Take three issues plaguing America today: Homelessness, medical debt, and student debt.

In the U.S. there are 550,000 homeless people. What percentage of those homeless simply can’t afford first month’s rent and a security deposit? According to Forbes, there are more than 600 billionaires in America. Anyone want to hire someone to change 1,500 lives a day and wipe out homelessness in America? How’s that for a legacy?

Want another staggering number? 530,000 families declare bankruptcy each year because of medical debt. Only 40% of Americans have enough savings to cover an emergency of $1,000. Want to change thousands of lives immediately? Set up a fund and just wipe this problem out.

Student debt may be the biggest problem of all where little things can go a long way. There is $1.5 trillion in federal student loan debt. That’s an unfathomable number. But next time you want to give an endowment to your alma mater, maybe think about why your old school is charging so much and just give the money to the students who need it most.

Go ahead and buy your jet, and your sports franchise, and your private island. You earned it. But at the same time, change 100 lives a day. Hell, change 1,000. Pay off 10,000 car leases. Give 4,000 families a security deposit to move into a house or an apartment. Pay 100,000 gas bills for the month. There are a million little things that can change people’s lives in immeasurable ways that you’re not even thinking about.

And if you’re Jeff Bezos? Or a Koch brother? Or a Walton? For every person’s student debt you wipe out, you create a customer for the rest of their lives.

This isn’t hard. Bezos earns more than $20 million a day. Hire 10 people and pay them all $250,000 a year. That’s $700 a day for each of them or $7,000 a day if you multiply by 10. That comes out to around $2.5 million a year. Remember, you make $20 million a day.

Tell those new hires that their job is to change 1,000 lives a month. 10 people, 1,000 lives each, for a grand total of 120,000 lives a year. Pay off people’s debts, give them security deposits, help them with a car loan, and give them financial security. You just created 120,000 Amazon customers for life, and you won’t even know the money is gone. And that’s if you’re barely even trying.

So, billionaires, again, congrats on making it. And again, shame on you for keeping it. You want a legacy for the world to remember?

It’s time to start thinking small.