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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1967 | 1 |
| 1969 | 2 |
| 1970 | 5 |
| 1971 | 18 |
| 1972 | 15 |
| 1973 | 35 |
| 1974 | 33 |
| 1975 | 40 |
| 1976 | 41 |
| 1977 | 35 |
| 1978 | 45 |
| 1979 | 98 |
| 1980 | 117 |
| 1981 | 75 |
| 1982 | 71 |
| 1983 | 142 |
| 1984 | 110 |
| 1985 | 84 |
| 1986 | 129 |
| 1987 | 98 |
| 1988 | 115 |
| 1989 | 117 |
| 1990 | 125 |
| 1991 | 148 |
| 1992 | 130 |
| 1993 | 114 |
| 1994 | 131 |
| 1995 | 103 |
| 1996 | 88 |
| 1997 | 96 |
| 1998 | 100 |
| 1999 | 93 |
| 2000 | 105 |
| 2001 | 93 |
| 2002 | 90 |
| 2003 | 109 |
| 2004 | 136 |
| 2005 | 110 |
| 2006 | 121 |
| 2007 | 133 |
| 2008 | 138 |
| 2009 | 112 |
| 2010 | 138 |
| 2011 | 152 |
| 2012 | 140 |
| 2013 | 126 |
| 2014 | 142 |
| 2015 | 123 |
| 2016 | 110 |
| 2017 | 96 |
| 2018 | 96 |
| 2019 | 94 |
| 2020 | 97 |
| 2021 | 95 |
| 2022 | 74 |
| 2023 | 87 |
| 2024 | 64 |
| 2025 | 37 |