I have a column with datetimes of different days with different times and I want to know how many different days are in that column. I got it to work in OpenOffice on an English system but it does not work anymore on an Italian or German system with Microsoft Excel:

```
=SUMPRODUCT((IF(FREQUENCY(DATEVALUE(MONTH(A1:A9)&"/"&DAY(A1:A9)&"/"&YEAR(A1:A9)),DATEVALUE(MONTH(A1:A9)&"/"&DAY(A1:A9)&"/"&YEAR(A1:A9))),TRUE())>0)*(MONTH(A1:A9)=6))
```

And that's what my column looks like

```
2016-06-29 19:50:00
2016-06-29 20:00:00
2016-06-29 11:34:00
2016-06-29 11:34:24
2016-06-29 12:33:29
2016-06-29 20:47:00
2016-06-30 11:46:46
2016-07-01 13:11:55
2016-07-01 13:12:26
```

For these values I would expect the formula to return 3, because there are 3 different days.

Finally I would like to amend the formula so that I can filter it by month - so that I can say: 'give me the number of distinct dates in june' and it returns 2.