There are seven tables in this data release, grouped by geographic summary level. The file names are:

• Nation (summary level 010)
• State (summary level 040)
• County (summary level 050, based on boundaries as of January 1, 2015)
• Place (summary level 160, based on boundaries as of January 1, 2015)
• MCD (Minor Civil Division, summary level 060, for the 12 strong MCD states: CT, ME, MA, NH, RI, VT, MI, WI, NJ, NY, MN, and PA, based on boundaries as of January 1, 2015)
• Tract (summary level 140, based on boundaries as of January 1, 2015)
• BlockGr (summary level 150, based on boundaries as of January 1, 2015)

Note that several county codes changed from 2014 to 2015. In those cases, the tracts and block groups in those areas stayed the same. For more information on those changes, see http://www.census.gov/geo/reference/county-changes.html. Note that the county and county-equivalent name changes that took place in 2015 are included with their new names and FIPS codes in the 2011-2015 ACS.