| Vlaams and Waals Brabant (Belgium) | Larmuseau et al., 2011 | 135 | 0 | 0 |
| Xingjiang | Zhong et al., 2011 | 244 | 11 | 4.51 |
| Xinjiang | Zhong et al., 2011 | 61 | 0 | 0 |
| Yakut | Sengupta et al., 2006 | 18 | 0 | 0 |
| Yemen | Cadenas et al., 2008 | 62 | 0 | 0 |
| Yunnan | Zhong et al., 2011 | 447 | 7 | 1.57 |
| Zhejiang | Zhong et al., 2011 | 102 | 2 | 1.96 |