Max Date from Rolling selection

[#1]

Hi
I have a list box with the Field MonthYear
It has data as follows

MAr-13

Apl-13

May-13

Jun-13

.

.

.

Aug-14

And I have a field

[maxgro · Accepted solution]

expression used for textbox

=if(GetPossibleCount(YearMonth)=1, Comment,

subfield(concat(distinct Comment, '@', -YearMonth),'@') )

[#3]

Worked perfectly TY