1910    24.000
1911    27.120
1912    34.040
1913    19.280
1914    20.220
1915    21.960
1916    29.280
1917    34.340
1918    11.260
1919    19.460
1920    18.780
1921    28.360
1922    18.980
1923    17.700
1924    31.200
1925    14.700
1926    19.580
1927    20.200
1928    12.080
1929    26.240
1930    13.900
1931    29.340
1932    15.040
1933    22.400
1934    39.360
1935    13.980
1936    18.380
1937    14.560
1938    18.320
1939    18.860
1940    24.060
1941    30.040
1942    12.640
1943    11.220
1944    12.240
1945    11.940
1946    14.560
1947     8.500
1948    16.020
1949    17.320
1950    24.960
1951    24.100
1952    12.380
1953    21.980
1954    29.860
1955    19.900
1956    19.820
1957    15.880
1958    23.000
1959    12.560
1960    13.800
1961    14.240
1962     8.200
1963    17.680
1964    18.740
1965    14.220
1966    16.860
1967     8.200
1968    14.720
1969    12.140
1970     7.640
1971    10.180
1972    14.280
1973    20.740
1974    10.640
1975    17.620
1976    21.780
1977    10.480
1978    20.520
1979    25.680
1980    10.980
1981    21.400
1982    19.900
1983    28.800
1984    16.220
1985    20.040
1986    19.760
1987    22.600
1988    17.440
1989    20.040
1990    24.760
1991    19.580
1992    21.480
1993    25.080
1994    14.980
1995    17.960
1996    32.180
1997    19.600
1998    41.720
1999    27.940
2000    17.960
2001    22.880
2002    21.980
2003    26.280
2004    19.740
2005    24.100
2006    34.640
2007    32.020
2008    20.980
2009    17.440
2010    24.600
2011    29.000
2012    50.160