*Excludes Observations that spanned multiple years

Pre 19700
19700
19710
19720
19730
19740
19750
19760
19770
19780
19790
19800
19810
19820
19830
19840
19850
19862
19870
19880
19897
19900
19910
19925
19935
19940
199512
19960
19971
19988
19991
20003
20015
20021
20031
200433
200517
20060
20071
200811
20090
201036
201152
20120
20136
20142
20150
20160
20170
Total209