However, Oppenheimer's net worth has risen by $750 million since the start of the year.
The Ackerman family owns a significant 25.53-percent stake in the leading retailer, totaling 124,677,238 ordinary shares.
The sum is 33-percent less than in 2021.
Ezz, who founded Ezz Steel in 1994, owns 60.7 percent of the company.
The most recent addition to the list is U.S. businesswoman Emma Grede.
Coumantaros owns a majority 63.34-percent stake in the agro group.
Elumelu owns a sizable 6.96-percent stake in the banking group.
This is the latest comment by the Egyptian billionaire on the Russia-Ukraine crisis.
Karanja founded the Kenyan brewer in 1997.
The recent forecast comes amid changing dynamics in developed economies.