Calculate min value of a date in column based on criteria

[Hermann01]

Hi All,

I al struggling with an issue I can't solve, hope you will be smarter than I am...

I have a table, ProductLocationData, with 3 columns: Product IDs, Countries, and Month, and I need to know in a fourth column what is the first date for each combination of Product ID + Country. Hereunder an example of what I want to achieve, in the last column.
I tried the following formula (among other tests), which doesn't work:

First Date formula:
=calculate(MIN([Month]);FILTER(Month;ProductLocationData[Product ID] = [Product ID] && ProductLocationData[Country] = [Country] && MIN
(ProductLocationData[CycleDate]) = ProductLocationData[CycleDate]))

Any idea?

Table name ProductLocationData​

[TABLE="class: grid, width: 500, align: center"]
<tbody>[TR]
[TD]Product ID[/TD]
[TD]Country[/TD]
[TD]Month[/TD]
[TD]First Date?[/TD]
[/TR]
[TR]
[TD]123[/TD]
[TD]Denmark[/TD]
[TD]01/01/2013[/TD]
[TD]01/01/2013[/TD]
[/TR]
[TR]
[TD]123[/TD]
[TD]Denmark[/TD]
[TD]01/02/2013[/TD]
[TD]01/01/2013[/TD]
[/TR]
[TR]
[TD]123[/TD]
[TD]Denmark[/TD]
[TD]01/03/2013[/TD]
[TD]01/01/2013[/TD]
[/TR]
[TR]
[TD]123[/TD]
[TD]Sweden[/TD]
[TD]01/01/2013[/TD]
[TD]01/01/2013[/TD]
[/TR]
[TR]
[TD]123[/TD]
[TD]Sweden[/TD]
[TD]01/02/2013[/TD]
[TD]01/01/2013[/TD]
[/TR]
[TR]
[TD]123[/TD]
[TD]Finland[/TD]
[TD]01/02/2013[/TD]
[TD]01/02/2013[/TD]
[/TR]
[TR]
[TD]123[/TD]
[TD]Finland[/TD]
[TD]01/03/2013[/TD]
[TD]01/02/2013[/TD]
[/TR]
[TR]
[TD]124[/TD]
[TD]Denmark[/TD]
[TD]01/01/2012[/TD]
[TD]01/01/2012[/TD]
[/TR]
[TR]
[TD]124[/TD]
[TD]Denmark[/TD]
[TD]01/02/2012[/TD]
[TD]01/01/2012[/TD]
[/TR]
</tbody>[/TABLE]

 

[Hermann01]

reading some other posts in your forum I finally tried:
=calculate(MIN([Month]);FILTER(ALL(ProductLocationData);[Product ID] = earlier([Product ID]) && [Country] = earlier([Country])))
AND
=calculate(MAX([Month]);FILTER(ALL(ProductLocationData);[Product ID] = earlier([Product ID]) && [Country] = earlier([Country])))

To get the first and the last date for each combination. It seams that it works.
If you can confirm, or have a better idea