| year | Vietnam | Cambodia | Lao PDR | Myanmar |
| 1995 | 1780 (76.2) | 151 | 88 | 318 |
| 1997 | 2587 (69.5) | 168 | 86 | 879 |
| 1998 | 1700 (63.6) | 243 | 45 | 683 |
| 1999 | 1484 (71.6) | 232 | 52 | 304 |
| 2000 | 1289 (76.7) | 149 | 34 | 208 |
| 2005 | 2021 (75.8) | 381 | 28 | 236 |
| 2010 | 8000 (70.4) | 783 | 333 | 2249 |
| 2011 | 7519 (69.8) | 892 | 301 | 2057 |
| 2012 | 8368 (72.3) | 1557 | 294 | 1354 |
| 2013 | 8900 (67.3) | 1275 | 427 | 2621 |
| 1995-2013 | 77,330 (73.6) | 9339 | 2960 | 15,497 |