The 2015 National Content Test was conducted by the U.S. Census Bureau to test census questionnaire content and to obtain nationwide measurements of response rates for Internet and self-response. The test census was sent to a statistically representative sample of approximately 1.2 million households in the United States and Puerto Rico. This test was scheduled to begin on August 24, and run through October 31, 2015. The official National Content Test Census Day was September 1, 2015.