Google Books Ngram Viewer

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

1800 - 1810 1811 - 1824 1825 - 1882 1883 - 1989 1990 - 2008 warum German
1800 - 1830 1831 - 1885 1886 - 1901 1902 - 1988 1989 - 2008 weshalb German
1800 - 1809 1810 - 1817 1818 - 1870 1871 - 1987 1988 - 2008 weswegen German

Run your own experiment! Raw data is available for download here.
© 2013 Google - Privacy & Terms - About Google - About Google Books - About Ngram Viewer