*Excludes Observations that spanned multiple years

Pre 19701
19700
19710
19720
197336
1974264
1975324
1976192
197736
1978132
1979120
198096
198187
198272
1983183
1984385
1985216
1986120
1987108
198896
198997
199096
199160
199287
199375
199476
199578
199685
199777
199885
199990
200091
200158
200288
200383
200479
200578
2006148
2007143
2008138
2009160
2010171
2011123
2012132
2013128
20142
20150
20160
20170
Total4996