*Excludes Observations that spanned multiple years

Pre 19701
19700
19711
19720
19730
19740
19750
19761
19770
19781
19790
19801
19812
19820
19830
19840
19850
19860
19870
19880
19890
19900
19910
19920
19932
19940
19950
19960
1997515
199826
199983
2000487
2001184
2002305
2003258
200480
200526
200616
200738
20081
20091
20107
20117
201213
201334
201467
2015188
20165
201717
20182
Total2369