| Value | Category | Cases | |
|---|---|---|---|
| 2012 | 1 |
0.1%
|
|
| 2013 | 1 |
0.1%
|
|
| 2014 | 234 |
15.5%
|
|
| 2015 | 615 |
40.8%
|
|
| 2017 | 183 |
12.1%
|
|
| 2018 | 472 |
31.3%
|
|
| 9999 | 9999. Missing | 1 |
0.1%
|
| Sysmiss | 237 |