*Excludes Observations that spanned multiple years

Pre 19704
19700
19710
19720
19730
19740
19750
19761
19770
19780
19790
19800
19810
19820
19830
19840
19850
19860
19870
19880
19890
19900
199124
199219
199327
19942
19954
19968
199717
199811
19994
20007
20017
200210
20039
200431
20058
20061
20071
200811
200928
201018
20112
20129
20134
20143
20150
20160
20170
Total270