Google Books Ngram Viewer

Graph these comma-separated phrases:
case-insensitive
between and from the corpus with smoothing of .  
Search in Google Books:

1900 - 1929 1930 - 1972 1973 - 1977 1978 - 1992 1993 - 2000 overpopulation English
1900 - 1963 1964 - 1972 1973 - 1974 1975 - 1996 1997 - 2000 population control English

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