1840		-8.5661
1842.5	-9.048 
1845		-9.028
1847.5	-8.676
1850		-8.961
1852.5	-8.476
1855		-7.733
1857.5	-7.7303
1860		-7.060 
1862.5	-5.933 
1865		-5.920 
1867.5	-5.296 
1870		-4.297 
1872.5	-4.555 
1875		-3.994 
1877.5	-2.979 
1880		-3.197 
1882.5	-2.574 
1885		-1.554 
1887.5	-1.840 
1890		-1.819 
1892.5	-1.565 
1895		-1.981 
1897.5	-1.386 
1900		-0.495 
1902.5	-0.540 
1905		-0.823 
1907.5	-1.5650
1910		-2.7578
1912.5	-3.6481
1915		-4.2847
1917.5	-4.6803
1920		-5.4042
1922.5	-5.8092
1925		-6.0432
1927.5	-6.3627
1930		-6.5348
1932.5	-6.3271
1935		-5.8398
1937.5	-5.8491
1940		-5.8493
1942.5	-5.7387
1945		-5.3583
1947.5	-5.5345
1950		-5.5270
1952.5	-5.3597
1955		-6.0454
1957.5	-5.9644
1960		-5.3984
1962.5	-5.2508
1965		-4.3351
1967.5	-3.2817
1970		-3.1235
1972.5	-2.6982
1975		-2.5018
1977.5	-3.7217
1980		-4.0370
1982.5	-3.3787
1985		-4.177
1987.5	-4.8577