Oil strikes it rich on Fortune 500 list

Oil companies have continued their domination over the rankings of the world's largest companies.

With the crude price spending much of the year to March above $US100 a barrel, oil companies took up six of the top 10 companies measured by revenue, according to the latest Fortune Global 500.

Royal Dutch Shell retained its top spot, with $US481.7 billion ($524.8 billion) in revenues, while Walmart rose from third in last year's ranking to take the No.2 position from Exxon Mobil.

Rounding out the top 10 oil contingent were Sinopec Group at No.4, China National Petroleum (5), British Petroleum (6) and France's Total (10).

While Exxon recorded the biggest profit, $US44.9 billion, Apple's profit margin dwarfed any other company in the top 20.

With revenues of $US156.5 billion, Apple recorded a $US41.7 billion profit, a 26.6 per cent return margin. Despite its recent fall from shareholder grace, Apple is still riding high as the second-most profitable company in the world.

Fortune ranked the world's 500 largest companies by revenue, a measure which puts Apple in 19th spot. It was ranked at No.55 last year. Since hitting a peak of $US702.10 in September, Apple shares have fallen 40.9 per cent to $US415.05. But according to Fortune, Apple has done anything but slow down. "The introductions of the iPhone 5 and the iPad Mini helped propel the tech giant's revenues up from $US108 billion in 2011 to $US157 billion last year," it said.

Despite being in the throes of an economic recovery, US companies maintained their lead in the rankings, taking up 132 places on the list. China came in second with 89 companies.

Samsung will be boasting its position over rival Apple, sliding in at 14th in terms of revenue.

"For Samsung, 2012 proved another banner year. While the South Korean electronics maker remained unchallenged in the TV business for the seventh consecutive year, it also became the No.1 mobile phone maker," Fortune said.

There were eight Australian companies in this year's rankings, down from nine last year.

Australia's top-ranked company was BHP Billiton at No.115, with $US72.2 billion in revenues producing $US15.4 billion in profit.

Conglomerates Wesfarmers and Woolworths followed at No.153 and No.159 respectively.

The big four banks and Telstra were Australia's other ranked companies.