Oklahoma City is the capital and largest city of the state of Oklahoma. The county seat of Oklahoma County, the city ranks 27th among United States cities in population. The population grew following the 2010 Census, with the population estimated to have increased to 610,613 as of July 2013. As of 2013, the Oklahoma City metropolitan area had a population of 1,319,677. More from Wikipedia.
Census Overview- The 2010 Census represented the most massive participation movement ever witnessed in our country. Approximately 74 percent of the households returned their census forms by mail; the remaining households were counted by census workers walking neighborhoods throughout the United States.