Show maximum Yearmonth Value selected in the Dropdown.

Hi jishnubhattacha 

As per my understanding of your requirement, could you please try the steps below?

1. disconnected table which you have already created .
Disconnected_YearMonth =
DISTINCT(FactTable[YearMonth])

2. Create a 1st measure .
Selected YearMonth =
VAR SelectedYM =
SELECTEDVALUE(Disconnected_YearMonth[YearMonth])
RETURN
IF(
ISBLANK(SelectedYM),
MAX(FactTable[YearMonth]),
SelectedYM
)


3.  Third measure.
Total Sales (Selected YM) =
CALCULATE(
SUM(FactTable[Sales]),
FactTable[YearMonth] = [Selected YearMonth]
)




If this answers your questions, kindly accept it as a solution and give kudos.