| Data Item | 1973 | 1974 | 1975 | 1976 | 1977 | 1978 | 1979 | 1980 | 1981 | 1982 | 1983 | 1984 | 1985 | 1986 | 1987 | 1988 | 1989 | 1990 | 1991 | 1992 | 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | 1999 | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Total number of houses built with air conditioning | 582,000.00 | 451,000.00 | 403,000.00 | 511,000.00 | 679,000.00 | 797,000.00 | 784,000.00 | 598,000.00 | 530,000.00 | 416,000.00 | 642,000.00 | 723,000.00 | 746,000.00 | 775,000.00 | 801,000.00 | 810,000.00 | 785,000.00 | 731,000.00 | 628,000.00 | 738,000.00 | 806,000.00 | 912,000.00 | 846,000.00 | 916,000.00 | 917,000.00 | 957,000.00 | 1,072,000.00 | 1,060,000.00 | 1,081,000.00 | 1,155,000.00 | 1,223,000.00 | 1,378,000.00 | 1,463,000.00 | 1,476,000.00 | 1,093,000.00 | 727,000.00 | 460,000.00 | 436,000.00 | 395,000.00 | 432,000.00 | 518,000.00 | 565,000.00 | 600,000.00 | 686,000.00 | 742,000.00 | 783,000.00 | 849,000.00 | 870,000.00 |
| Total number of houses built without air conditioning | 616,000.00 | 489,000.00 | 473,000.00 | 523,000.00 | 579,000.00 | 572,000.00 | 517,000.00 | 358,000.00 | 289,000.00 | 216,000.00 | 282,000.00 | 302,000.00 | 326,000.00 | 346,000.00 | 322,000.00 | 275,000.00 | 241,000.00 | 235,000.00 | 210,000.00 | 225,000.00 | 234,000.00 | 248,000.00 | 219,000.00 | 213,000.00 | 199,000.00 | 203,000.00 | 198,000.00 | 181,000.00 | 175,000.00 | 170,000.00 | 164,000.00 | 153,000.00 | 173,000.00 | 179,000.00 | 125,000.00 | 92,000.00 | 61,000.00 | 60,000.00 | 52,000.00 | 51,000.00 | 51,000.00 | 55,000.00 | 48,000.00 | 53,000.00 | 53,000.00 | 57,000.00 | 54,000.00 | 42,000.00 |
The single-family statistics include fully detached, semidetached (semiattached, side-by-side), row houses, and townhouses. In the case of attached units, each must be separated from the adjacent unit by a ground-to-roof wall in order to be classified as a single-family structure. Also, these units must not share heating/air-conditioning systems or utilities.
Units built one on top of another and those built side-by-side that do not have a ground-to-roof wall and/or have common facilities (i.e., attic, basement, heating plant, plumbing, etc.) are not included in the single-family statistics.
Source: U.S. Census Bureau