Year	Number of Buildings
1960-01-01	18000.00
1961-01-01	19100.00
1962-01-01	23150.00
1963-01-01	21700.00
1964-01-01	24225.00
1965-01-01	23250.00
1966-01-01	23525.00
1967-01-01	24950.00
1968-01-01	26850.00
1969-01-01	26375.00
1970-01-01	22177.50
1971-01-01	26146.25
1972-01-01	24653.00
1973-01-01	20046.75
1974-01-01	20245.75
1975-01-01	12836.25
1976-01-01	14304.50
1977-01-01	13488.50
1978-01-01	14323.50
1979-01-01	14009.00
1980-01-01	12527.75
1981-01-01	11113.50
1982-01-01	10482.25
1983-01-01	9444.00
1984-01-01	8517.00
1985-01-01	6884.75
1986-01-01	7691.50
1987-01-01	9953.50
1988-01-01	12705.75
1989-01-01	14719.75
1990-01-01	17406.50
1991-01-01	14213.75
1992-01-01	12365.75
1993-01-01	2977.75
1994-01-01	2965.00
1995-01-01	3183.75
1996-01-01	3189.25
1997-01-01	2993.00
1998-01-01	3157.75
1999-01-01	3642.25
2000-01-01	4205.75
2001-01-01	4850.25
2002-01-01	4762.75
2003-01-01	5513.00
2004-01-01	6829.75
2005-01-01	7946.75
2006-01-01	11316.00
2007-01-01	6892.50
2008-01-01	5303.75
2009-01-01	4492.50
2010-01-01	6887.75
2011-01-01	6682.25
2012-01-01	5330.25
2013-01-01	7628.50
2014-01-01	9185.25
2015-01-01	11976.00
2016-01-01	15001.50
2017-01-01	15870.75