| Year | Volume | Number |
|---|---|---|
| 2023 | 47 | 31 articles special issue |
| 2022 | 46 | 48 articles |
| 2021 | 45 | 53 articles |
| 2020 | 44 | 64 articles |
| 2019 | 43 | 51 articles |
| 2018 | 42 | 78 articles |
| 2017 | 41 | 83 articles |
| 2016 | 40 | 103 articles |
| 2015 | 39 | 1 2 3 4 5 6 |
| 2014 | 38 | 1 2 3 4 5 6 |
| 2013 | 37 | 1 2 3 4 5 6 |
| 2012 | 36 | 1 2 3 4 5 6 |
| 2011 | 35 | 1 2 3 4 5 6 |
| 2010 | 34 | 1 2 3 4 5 6 |
| 2009 | 33 | 1 2 3 4 5 6 |
| 2008 | 32 | 1 2 3 4 5 6 special issue |
| 2007 | 31 | 1 2 3 4 5 6 |
| 2006 | 30 | 1 2 3 4 5 6 |
| 2005 | 29 | 1 2 3 4 5 6 |
| 2004 | 28 | 1 2 3 4 5 6 |
| 2003 | 27 | 1 2 3 4 5 6 |
| 2002 | 26 | 1 2 3 4 |
| 2001 | 25 | 1 2 3 4 |
| 2000 | 24 | 1 2 3 4 |
| 1999 | 23 | 1 2 3 4 |
| 1998 | 22 | 1 2 3 4 |
| 1997 | 21 | 3 4 |
