2 ) Sultan Hassanal Bolkiah of Brunei – $20 billion

Sultan Hassanal Bolkiah has been head of state since 1967. He led his country through the global recession; however with oil reserves expected to last only a further 25 years, his focus is now on diversifying the country’s economy to avoid disaster when reserves run out. He is also infamous for his car collection, with rumours he owns over 7,000 cars costing a grand total of $789 million. According to Guinness World Records his collection has more than 600 Rolls-Royces, 450 Ferraris and 134 Koenigseggs, making it the largest brand collection in the world. In fact, during the 1990s his family accounted for almost half of Rolls-Royce’s global sales as his family looked to add to and diversify their collection.