*Excludes Observations that spanned multiple years

Pre 197032
19701
19712
19720
19730
19741
19750
19761
19771
19780
19791
19802
19810
19820
19831
19840
19850
19860
19870
19883
198918
19900
19910
19923
19930
19940
19959
19961
19978
199812
19998
2000162
200176
200253
2003790
2004281
2005294
2006390
2007344
2008177
20094069
201072
2011606
2012149
2013102
2014335
2015226
2016194
201776
20183
Total8503