*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19731
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19908
19910
19924
19930
19943
19952
19961
19978
19981
19992
200012
200112
200210
200320
200420
200524
200616
20078
200821
20093
20104
20114
20127
20130
20140
20150
20160
20170
Total191