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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1959 | 2 |
| 1962 | 1 |
| 1966 | 15 |
| 1967 | 30 |
| 1969 | 45 |
| 1970 | 15 |
| 1971 | 29 |
| 1972 | 17 |
| 1973 | 11 |
| 1974 | 103 |
| 1975 | 179 |
| 1976 | 92 |
| 1977 | 106 |
| 1978 | 107 |
| 1979 | 127 |
| 1980 | 114 |
| 1981 | 121 |
| 1982 | 107 |
| 1983 | 70 |
| 1984 | 131 |
| 1985 | 156 |
| 1986 | 158 |
| 1987 | 97 |
| 1988 | 151 |
| 1989 | 107 |
| 1990 | 82 |
| 1991 | 83 |
| 1992 | 67 |
| 1993 | 71 |
| 1994 | 59 |
| 1995 | 88 |
| 1996 | 75 |
| 1997 | 86 |
| 1998 | 70 |
| 1999 | 1 |
| 2000 | 1 |
| 2001 | 37 |
| 2002 | 62 |
| 2003 | 66 |
| 2004 | 7 |
| 2006 | 9 |
| 2007 | 48 |
| 2008 | 34 |
| 2009 | 26 |
| 2010 | 23 |
| 2011 | 19 |
| 2012 | 6 |
| 2016 | 13 |
| 2017 | 29 |
| 2018 | 24 |
| 2019 | 18 |
| 2020 | 44 |
| 2021 | 34 |
| 2022 | 34 |
| 2023 | 21 |
| 2024 | 31 |
| 2025 | 31 |