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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1958 | 1 |
| 1961 | 4 |
| 1964 | 1 |
| 1965 | 4 |
| 1966 | 11 |
| 1967 | 13 |
| 1968 | 10 |
| 1969 | 18 |
| 1970 | 18 |
| 1971 | 12 |
| 1972 | 22 |
| 1973 | 26 |
| 1974 | 37 |
| 1975 | 29 |
| 1976 | 30 |
| 1977 | 29 |
| 1978 | 51 |
| 1979 | 62 |
| 1980 | 58 |
| 1981 | 61 |
| 1982 | 83 |
| 1983 | 83 |
| 1984 | 77 |
| 1985 | 100 |
| 1986 | 106 |
| 1987 | 99 |
| 1988 | 112 |
| 1989 | 134 |
| 1990 | 112 |
| 1991 | 79 |
| 1992 | 95 |
| 1993 | 85 |
| 1994 | 89 |
| 1995 | 92 |
| 1996 | 102 |
| 1997 | 106 |
| 1998 | 88 |
| 1999 | 100 |
| 2000 | 89 |
| 2001 | 90 |
| 2002 | 100 |
| 2003 | 91 |
| 2004 | 90 |
| 2005 | 70 |
| 2006 | 35 |
| 2007 | 45 |
| 2008 | 52 |
| 2009 | 64 |
| 2010 | 61 |
| 2011 | 62 |
| 2012 | 39 |
| 2013 | 50 |
| 2014 | 55 |
| 2015 | 42 |
| 2016 | 33 |
| 2017 | 39 |
| 2018 | 44 |
| 2019 | 48 |
| 2020 | 28 |
| 2021 | 17 |
| 2022 | 19 |
| 2023 | 17 |
| 2024 | 25 |
| 2025 | 10 |