Era
1978-1989
116
1994-
114
1961-1991
72
1989-1994
63
1978-
60
1991-
55
20th century
49
1961-
40
1961-1994
40
1961-1978
38
1975-1994
22
1948-1961
19
1960-
19
21st century
18
1975-
17
Since 1994
14
Since 1961
13
1918-1961
12
1989-
12
Since 1991
11
1948-1994
10
1909-1948
9
2000-2099
9
Since 1960
8
1946-1990
7
1948-
7
Since 1978
7
1836-1909
6
1945-
6
1564-1616
5
1945-1989
5
1961 - 1991
5
1978 - 1989
5
1978-1994
5
Since 1989
5
1900-1999
4
Precambrian
4
1918-
3
1946-
3
1966-
3
To 1836
3
1870-1950
2
1880-1910
2
1900-2099
2
1909-
2
1955-1965
2
1961 - 1994
2
Since 1948
2
-1914
1
1789-1900
1
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