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Table representation of search results timeline featuring number of search results per year.
| Year | Number of Results |
|---|---|
| 1957 | 1 |
| 1968 | 1 |
| 1969 | 1 |
| 1970 | 2 |
| 1972 | 31 |
| 1973 | 128 |
| 1974 | 190 |
| 1975 | 163 |
| 1976 | 362 |
| 1977 | 387 |
| 1978 | 415 |
| 1979 | 424 |
| 1980 | 606 |
| 1981 | 589 |
| 1982 | 794 |
| 1983 | 819 |
| 1984 | 939 |
| 1985 | 1128 |
| 1986 | 1108 |
| 1987 | 1057 |
| 1988 | 1175 |
| 1989 | 1272 |
| 1990 | 1411 |
| 1991 | 1346 |
| 1992 | 1448 |
| 1993 | 1417 |
| 1994 | 1148 |
| 1995 | 1349 |
| 1996 | 1212 |
| 1997 | 1205 |
| 1998 | 1037 |
| 1999 | 952 |
| 2000 | 1127 |
| 2001 | 1002 |
| 2002 | 931 |
| 2003 | 790 |
| 2004 | 724 |
| 2005 | 827 |
| 2006 | 817 |
| 2007 | 914 |
| 2008 | 923 |
| 2009 | 621 |
| 2010 | 588 |
| 2011 | 504 |
| 2012 | 536 |
| 2013 | 497 |
| 2014 | 490 |
| 2015 | 543 |
| 2016 | 408 |
| 2017 | 422 |
| 2018 | 488 |
| 2019 | 425 |
| 2020 | 445 |
| 2021 | 417 |
| 2022 | 104 |
| 2023 | 23 |
| 2024 | 8 |