Era
20th century
8,217
1900-1999
2,779
19th century
2,711
21st century
1,224
1900 - 1999
1,067
To 1846
1,017
1846-1850
907
1850-1950
637
1800-1899
566
1951-
520
2000-2099
497
20e siècle
403
Civil War, 1861-1865
262
18th century
239
Tertiary
229
1947-
217
1800 - 1899
206
Miocene
203
1939-1945
202
1950-
177
Pleistocene
176
1713-1784
175
Since 1951
170
Cenozoic
168
Quaternary
158
Pliocene
145
20e siècle
142
1944-
138
1934-
137
1800-1999
136
1900-2099
136
Cretaceous
136
1991
133
1961-1970
123
1970
123
1971-1980
120
1902-1968
115
1945-
114
1990
110
21e siècle
110
1994
109
1850
108
1803-1880
107
1927-1993
106
1989
103
From 2 to 65 million years ago
103
1992
101
Eocene
101
1861-1865
99
1946-
98
més ...