Donald Trump will reportedly become the richest U.S. president after he takes office Friday. Forbes estimates the real estate tycoon’s net worth to be $3.7 billion.

The president-elect’s annual earning is $60 million, according to Celebrity Net Worth. Last November, the 70-year-old said that he would forgo the $400,000 annual salary typically given to an American president. However, his net worth dropped by $800 million last year from $4.5 billion in 2015.

According to Forbes, the "softening" of the New York property market was the reason behind the plunge in his wealth. Of the 28 buildings that the magazine assessed, 18 declined in value, including the popular Trump Tower on Manhattan's Fifth Avenue. However, seven of his properties increased in value, according to Forbes. He reportedly invested about $50 million of his money in the presidential campaign.

Trump, who was born into a wealthy family, inherited about $40 million from his late father, real estate developer Fred Trump. In 1971, he took charge of what is now known as the Trump Organization. Since then, he has developed over 500 businesses, including hotels, condo towers, golf courses and foreign and domestic licensing deals.

In the 1970s, Trump reportedly got several deals, including the one with Hyatt and New York City. He then renovated and rebranded the hotel into the Grand Hyatt, which went on to become successful.

In 1984, the construction on the 68-story Trump Tower in New York City — home of the Trump Organization — was completed. He also had several businesses and properties, including Trump Place — a housing development project with 5,700 apartments throughout 18 buildings. The Trump International Hotel & Tower Chicago houses a hotel, condos and several restaurants and stores. Wollman Rink, a Central Park staple that sees more than 5 million visitors each year, is also owned by Trump.