The U.S. Census Bureau collects and distributes data under a handful of different programs. Two of the more commonly used programs are the Decennial Census and the American Community Survey (ACS). The Decennial Census is a definite source of demographic data but only is collected every ten years; it includes a limited number of variables such as number of households and total population. The ACS is a program that provides data estimates on a one, three, and five year timeline; ACS data is collected more frequently but the data estimates have a margin of error that must considered because the data is taken from a small sample of the total population. The ACS includes many more variables compared to the Decennial Census that relate to transportation, income, and housing. Both the Decennial and ACS datasets have similiar data structures. Each row in both datasets include a particular variable and a number the indicates the total number of households or persons that characterize that variable.