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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1964 | 1 |
| 1966 | 1 |
| 1968 | 16 |
| 1969 | 92 |
| 1970 | 271 |
| 1971 | 342 |
| 1972 | 360 |
| 1973 | 406 |
| 1974 | 409 |
| 1975 | 417 |
| 1976 | 468 |
| 1977 | 450 |
| 1978 | 444 |
| 1979 | 526 |
| 1980 | 581 |
| 1981 | 594 |
| 1982 | 564 |
| 1983 | 622 |
| 1984 | 625 |
| 1985 | 536 |
| 1986 | 547 |
| 1987 | 540 |
| 1988 | 540 |
| 1989 | 498 |
| 1990 | 516 |
| 1991 | 428 |
| 1992 | 481 |
| 1993 | 405 |
| 1994 | 394 |
| 1995 | 333 |
| 1996 | 337 |
| 1997 | 352 |
| 1998 | 282 |
| 1999 | 261 |
| 2000 | 225 |
| 2001 | 206 |
| 2002 | 203 |
| 2003 | 176 |
| 2004 | 189 |
| 2005 | 216 |
| 2006 | 168 |
| 2007 | 154 |
| 2008 | 138 |
| 2009 | 155 |
| 2010 | 154 |
| 2011 | 186 |
| 2012 | 158 |
| 2013 | 112 |
| 2014 | 161 |
| 2015 | 175 |
| 2016 | 147 |
| 2017 | 135 |
| 2018 | 138 |
| 2019 | 122 |
| 2020 | 85 |
| 2021 | 76 |
| 2022 | 84 |
| 2023 | 57 |
| 2024 | 28 |