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Table representation of search results timeline featuring number of search results per year.

Year Number of Results
1967 7
1968 8
1969 6
1970 5
1971 10
1972 22
1973 16
1974 7
1975 9
1976 10
1977 7
1978 5
1979 17
1980 12
1981 13
1982 15
1983 10
1984 12
1985 20
1986 31
1987 35
1988 48
1989 68
1990 73
1991 83
1992 85
1993 84
1994 115
1995 94
1996 81
1997 91
1998 120
1999 118
2000 115
2001 121
2002 143
2003 162
2004 143
2005 138
2006 201
2007 207
2008 215
2009 235
2010 192
2011 190
2012 205
2013 197
2014 182
2015 170
2016 151
2017 170
2018 167
2019 143
2020 127
2021 63
2022 3
2023 1
2024 27

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4,500 results

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Page 1
Effects of caffeine on human behavior.
Smith A. Smith A. Food Chem Toxicol. 2002 Sep;40(9):1243-55. doi: 10.1016/s0278-6915(02)00096-0. Food Chem Toxicol. 2002. PMID: 12204388 Review.
4,500 results