This as similarities spotted between Herman Cain’s 9-9-9 tax proposal and SimCity4. Cain’s plan calls for national 9 percent sales tax, a 9 percent tax on income, and another 9 percent on business profits. The default tax rate in SimCity4, which came out in 2003? 9 percent housing tax, 9 percent commercial tax, and a 9 percent factory tax. Kip Katsarelis helped develop the game, and the Huffington post captured his reaction to the news: “We encourage politicians to continue to look to innovative games like SimCity for inspiration for social and economic change.”