Not every article in a journal is considered primary research and therefore "citable", this chart shows the ratio of a journal's articles including substantial research (research articles, conference papers and reviews) in three year windows vs. those documents other than research articles, reviews and conference papers.
| Documents | Year | Value |
| Non-citable documents | 2008 | 36 |
| Non-citable documents | 2009 | 54 |
| Non-citable documents | 2010 | 79 |
| Non-citable documents | 2011 | 66 |
| Non-citable documents | 2012 | 112 |
| Non-citable documents | 2013 | 289 |
| Non-citable documents | 2014 | 505 |
| Non-citable documents | 2015 | 568 |
| Non-citable documents | 2016 | 619 |
| Citable documents | 2008 | 220 |
| Citable documents | 2009 | 407 |
| Citable documents | 2010 | 596 |
| Citable documents | 2011 | 549 |
| Citable documents | 2012 | 485 |
| Citable documents | 2013 | 414 |
| Citable documents | 2014 | 336 |
| Citable documents | 2015 | 340 |
| Citable documents | 2016 | 267 |