The 55-year-old tycoon sold 5.6 percent of his EBX Group Co. holding company to Abu Dhabi’s Mubadala Development Co. for $2 billion on March 26. That lifted him to eighth on the Bloomberg Billionaires Index, a daily ranking of the world’s richest people. He held the spot for three days before sliding back to 10th as shares of his oil producer, OGX Petroleo & Gas Participacoes SA, fell by 2.2 percent Friday.

“Eike’s business accomplishments demonstrate that Brazil is the real deal,” Eric Saucedo, a partner at New York-based merchant-banking firm Tricap Partners & Co., said in an e-mail. “You did not see this in previous years.”

Billionaire fortunes rose as global stocks posted the best first-quarter rally since 1998 amid signs of economic improvement in Europe and the U.S. The Standard & Poor’s 500 Index rose for the sixth week of the past seven, adding 0.8 percent to close at 1,408.47.

Mexican Carlos Slim, the richest man in the world, gained $1.5 billion during the week as his country’s benchmark IPC stock index reached a record. In a decision published March 27, antitrust regulators rejected his appeal against a ruling that could pave the way for increased regulation of his telecom operator, America Movil SAB. The 72-year-old has a net worth of $70.8 billion.

Gates, Buffett

Microsoft Corp. co-founder Bill Gates, 56, is second on the index with a net worth of $63.8 billion, up $664.5 million for the week. Warren Buffett, 81, is third with $45.4 billion. The world’s three richest people have gained a combined $19.6 billion year to date.

Among the biggest losers of the week was Stefan Persson, 64, chairman of Swedish clothing retailer Hennes & Mauritz AB. He lost $1.2 billion on March 29 after first-quarter profit at Europe’s second-biggest clothing retailer missed estimates. His $24.5 billion fortune makes him the world’s 13th-richest person.

Spanish retailer Amancio Ortega, sixth on the ranking, saw his fortune climb by $362.1 million to $40.6 billion as shares of his Industria de Diseno Textil SA, owner of the Zara fashion chain, gained 0.4 percent in Madrid. Ortega’s net worth is up 16 percent year to date.

Mukesh Ambani’s wealth rose $384.9 million to $24.3 billion as shares of Mumbai-based Reliance Industries Ltd., operator of the world’s biggest oil-refining complex, rose for the first time in five weeks, adding 0.9 percent. His company joined a rally for Indian stocks after the government issued a clarification for overseas investors on new tax proposals.