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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1955 | 1 |
| 1956 | 2 |
| 1958 | 2 |
| 1959 | 2 |
| 1960 | 2 |
| 1964 | 1 |
| 1965 | 2 |
| 1966 | 4 |
| 1967 | 10 |
| 1968 | 14 |
| 1969 | 16 |
| 1970 | 23 |
| 1971 | 22 |
| 1972 | 30 |
| 1973 | 30 |
| 1974 | 32 |
| 1975 | 39 |
| 1976 | 49 |
| 1977 | 51 |
| 1978 | 49 |
| 1979 | 61 |
| 1980 | 61 |
| 1981 | 54 |
| 1982 | 70 |
| 1983 | 69 |
| 1984 | 89 |
| 1985 | 75 |
| 1986 | 106 |
| 1987 | 110 |
| 1988 | 107 |
| 1989 | 117 |
| 1990 | 136 |
| 1991 | 180 |
| 1992 | 190 |
| 1993 | 152 |
| 1994 | 183 |
| 1995 | 191 |
| 1996 | 165 |
| 1997 | 180 |
| 1998 | 148 |
| 1999 | 171 |
| 2000 | 140 |
| 2001 | 149 |
| 2002 | 105 |
| 2003 | 111 |
| 2004 | 98 |
| 2005 | 129 |
| 2006 | 130 |
| 2007 | 97 |
| 2008 | 111 |
| 2009 | 91 |
| 2010 | 120 |
| 2011 | 119 |
| 2012 | 116 |
| 2013 | 108 |
| 2014 | 93 |
| 2015 | 72 |
| 2016 | 71 |
| 2017 | 59 |
| 2018 | 91 |
| 2019 | 66 |
| 2020 | 76 |
| 2021 | 49 |
| 2022 | 24 |
| 2023 | 18 |
| 2024 | 22 |