Arizona has represented the epicenter of school choice in the United States. The state has had open enrollment for district schools for 30 years, charter schools for more than 25 years, a private school tax credit program for nearly as long, and was the first state in the country in 2011 to enact direct parent-appropriations through targeted Empowerment Scholarship Account (ESA) vouchers. Arizona then became the first state to expand its ESA voucher program to be universal. In all, Arizona provides more than $1 billion annually in subsidies to private education, both to private schools and variations on homeschooling, all coming from the state's general fund directly or indirectly due to tax credits. Because Arizona has provided no accountability and little transparency for participating private entities receiving public subsidies, the Grand Canyon Institute's efforts aim to improve accountability and transparency. This paper will provide both a composite of the past research findings of GCI as well provide a new zip code analysis of users of the program as well as note an estimated portion not using ESA vouchers for private schooling. [This paper was prepared by the Grand Canyon Institute.]