While Elon Musk remains the world's richest person, his net wealth has been cut nearly in half from its $340 billion peak a year ago.

The chief of executive of Tesla (TSLA) and Twitter is worth about $177 billion, a 48% drop, according to the Bloomberg Billionaires Index. Musk has lost $92 billion this year, the index's biggest decline.

Musk hit his $340 billion peak when Tesla was trading at an all-time high of $410 a share. Tesla's share price plunged to a 52-week low of $186.75 on Tuesday. The carmaker's stock is down 45% for the year and some investors are concerned Musk is spreading himself too thin with his $44 billion acquisition of Twitter.

Major Twitter advertisers have paused their paid advertising on the social media platform until the company's direction is made clear.

Meanwhile, Tesla has struggled this year, challenged by rising interest rates, falling demand and economic pressures outside the U.S. It shuttered its flagship Beijing showroom and reduced prices in China.

Tesla reported third quarter earnings last month that missed analysts' expectations for revenue.

Shares of Tesla on Tuesday afternoon were at $191.65, down $5.43, or 2.76%.