Era
20th century
74
19th century
42
18th century
32
Quaternary
28
Precambrian
24
17th century
22
21st century
17
1879-1955
15
1564-1642
12
1809-1882
12
1885-1962
12
To 1500
11
Archaean
10
Cenozoic
10
1887-1920
9
Cretaceous
9
1854-1912
8
Holocene
8
Pleistocene
7
1642-1727
6
1646-1716
6
1946-
6
Jurassic
6
Proterozoic
6
1707-1783
5
1922-1996
5
Mesozoic
5
Neogene
5
Paleogene
5
Permian
5
1831-1879
4
1881-1966
4
1882-1935
4
1893-1956
4
1913-1996
4
1928-
4
1938-
4
1948-
4
1949-
4
16th century
3
1738-1822
3
1809-1877
3
1826-1866
3
1853-1928
3
1871-1953
3
1887-1961
3
1898-1979
3
1901-1954
3
1901-1981
3
1908-1968
3
more ...