From: The factualization of ‘I suppose’ in American English: a corpus based study of the subjectification of epistemic predicates toward factuality
1810
1820
1830
1840
1850
1860
1870
1880
1890
1990
1910
1920
1930
1940
1950
1960
maybe
1
2
5
4
perhaps
3
probably
likely