Valero Energy Corp. was chosen as the No. 1 Best Big Company to work for in the U.S., according to Fortune magazine’s annual ranking.

Out of 33 companies that were listed on the "Best Companies to Work For" list and the Fortune100 list, Fortune chose Valero as No. 1. On the Fortune 100 list itself, Valero ranked No. 67.

The magazine picked Valero because, it said, it was impressed with the fact the company makes its corporate jet available to employees facing medical emergencies and covers 100% of health insurance premiums.

Valero has 17,488 U.S. employees and its most common salaried job is the store manager for its retail store division. The company pays an average $97,730 in that position.

The San Antonio-based refiner-marketer was honored in 2006 by Convenience Store Decisions as the Convenience Store Chain of the Year.