这是例子，
+------+----+
| CARS | 3 |
| CARS | 4 |
| CARS | 6 |
| CARS | 76 |
| CARS | 4 |
| CARS | 3 |
| SUV | 32 |
| SUV | 3 |
| SUV | 3 |
| SUV | 2 |
| SUV | 3 |
| SUV | 5 |
+------+----+
我想添加一个新的计算列，其中包含这样的数据
+------+----+------+
| CARS | 3 | 96 |
| CARS | 4 | 96 |
| …