1. Search history detail.
| Year | Abstracts retrieved |
| Up to and including 1999 | 1340 |
| 2000 | 464 |
| 2001 | 131 |
| 2002 | 34 |
| 2003 | 72 |
| 2004 | 116 |
| 2005 | 48 |
| 2006 | 40 |
| 2007 | 62 |
| 2008 | 100 |
| 2009‐10 | 60 |
| 2011 | 77 |
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