Amgen is the largest employer in Thousand Oaks and second only to the United States Navy in terms of number of people employed in Ventura County. In 2004, BusinessWeek ranked Amgen first on the S&P 500 for being one of the most "future-oriented" of those five hundred corporations.[2] BusinessWeek ostensibly calculated the ratio of research and development spending, combined with capital spending, to total outlays; Amgen had the fourth highest ratio, at 506:1000.