(Fortune) -- Cigna (Charts) ranks no. 399 on FORTUNE's Global 500 this year, with $16.7 billion in revenues, down 8.2% from the previous year. The Philadelphia, Pennsylvania-based company was ranked no. 333 on the 2005 list. Its 2005 profits were $1.6 billion, up 13% from a year earlier.

2005 was a banner year for most Global 500 companies. It took $13.7 billion in revenue just to make this year's list - up from $12.4 billion last year. And profits for the 500 companies jumped 30%. Total revenues for the Global 500 in 2006 add up to $18.9 trillion, a third of the world's GDP. In the Health Care: Insurance & Managed Care industry, profits were up 13% from the previous year.

The world's biggest companies in the sector are: Wellpoint (Charts) , ranked no. 117 on the Global 500 with $45.1 billion in revenues; Aetna (Charts), ranked no. 271 on the Global 500 with $22.9 billion in revenues; and Humana (Charts), ranked no. 473 on the Global 500 with $14.4 billion in revenues.

The Global 500 list is an annual ranking of the world's largest corporations by revenues.

Next: Full list: 2006 Global 500 at //money.cnn.com/global500

Plus: See Cigna's Global 500 details, including financial stats and contact information.