State:
Alabama
Alaska
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
District of Columbia
Florida
Georgia
Hawaii
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Maine
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Montana
Nebraska
Nevada
New Hampshire
New Jersey
New Mexico
New York
North Carolina
North Dakota
Ohio
Oklahoma
Oregon
Pennsylvania
Rhode Island
South Carolina
South Dakota
Tennessee
Texas
Utah
Vermont
Virginia
Washington
West Virginia
Wisconsin
Wyoming
Census block group analysis
This sample loads census block group data for a state and then retrieves the intersection with an area drawn by the user and calculates an estimated population. Not only does it take into consideration the population of each census block group, but also the amount of overlap they have with the drawn area as well.
US Census 2010 data used in this sample:
Block Group Cartographic Boundary Files
Centers of Population by Block Group