Year per 1,000 people 1960 1.1 1961 1.1 1962 1.1 1963 1.1 1964 1.1 1965 1.2 1966 1.2 1967 1.2 1968 1.2 1969 1.2 1970 1.2 1971 1.3 1972 1.4 1973 1.4 1974 1.5 1975 1.6 1976 1.7 1977 1.7 1978 1.8 1979 1.8 1990 2.507 1991 2.597 1999 2.38 2000 2.447 2001 2.525 2002 2.59 2003 2.632 2004 2.662 2005 2.717 2006 2.799 2007 2.792 2008 2.868 2009 2.922 2010 2.963 2011 3.131 2012 3.248 2013 3.301 2014 3.407 2015 3.471 2016 3.517 2017 3.588 2018 3.661 2019 3.751 2020 3.836