The Unite States Academic Decathlon (USAD; often abbreviated to AD, Acadeca, Acadec, AcDec or even AcDc) is one of the premier academic competitions for high school students in the United States. USAD contests are held in 42 states. It consists of ten events, which include seven tests, two performance events and an essay. It was started by Dr. Robert Peterson in Orange County, California for local schools in 1968, but was expanded to a nation-wide competition in 1981.