Hello,
I have the following table.
| VisitID | PersonID | YEAR |
| 1 | 1 | 2014 |
| 2 | 1 | 2015 |
| 3 | 1 | 2016 |
| 4 | 1 | 2017 |
| 5 | 1 | 2018 |
| 6 | 1 | 2018 |
| 7 | 2 | 2015 |
| 8 | 2 | 2016 |
| 9 | 2 | 2017 |
| 10 | 3 | 2016 |
| 11 | 3 | 2017 |
| 12 | 3 | 2017 |
| 13 | 3 | 2018 |
| 14 | 4 | 2014 |
| 15 | 4 | 2015 |
| 16 | 4 | 2015 |
| 17 | 4 | 2016 |
| 18 | 4 | 2018 |
| 19 | 5 | 2016 |
| 20 | 5 | 2016 |
I want to count how many PersonID who had at least two VisitID during the period 2017-2018.
The answer should be 2 (PersonID 1 and PersonID 3) even if I make the selection 2018 for field YEAR.
Can anyone help me with this?
Best regards
