The 2007 American Community Survey (ACS) Grid-Sequential test provided data to help us decide the format of the basic demographic section of the 2008 ACS mail form. Specifically, the test helped determine whether the traditional AC S matrix/grid format for the basic demographic section of the mail form collects data that are different from data collected using the "€œperson box"/sequential format used in the decennial census. A second objective of this test was to determine whether moving the rostering instructions from page two next to the matrix to the cover of the form increased or decreased discrepancies between the count on the front of the form and the count of people provided in the basic demographic section.