我们有数千行数据,格式如下
| Name | Born On |
|:-----------|------------:|
| Tom | Jul 15 |
| Harry | Jul 15 |
| Katy | Oct 2 |
| Britney | Oct 2 |
| Miranda | Oct 2 |
| Victoria | Oct 2 |
| John | Sep 30 |
| Warren | Sep 30 |
| George | Sep 30 |
我想根据“Born On”列添加一个序列号如下
| Name | Born On | Serial Number
|:-----------|------------:|--------------:|
| Tom | Jul 15 | 1
| Harry | Jul 15 | 2
| Katy | Oct 2 | 1
| Britney | Oct 2 | 2
| Miranda | Oct 2 | 3
| Victoria | Oct 2 | 4
| John | Sep 30 | 1
| Warren | Sep 30 | 2
| George | Sep 30 | 3
“序列号”需要按“出生日期”分组。请帮忙。谢谢。