My data looks like
我的数据看起来像
+-------+-------+-------+------+
| Group | Count | Month | Year |
+-------+-------+-------+------+
| A | 102 | Jan | 2015 |
| B | 20 | Jan | 2016 |
| C | 30 | Feb | 2015 |
| A | 10 | Jan | 2016 |
| C | 20 | Feb | 2016 |
+-------+-------+-------+------+
+-------+-----
