How to return a single datetime from multiple rows of MAX(value) in DAX

Question

Hi
I have a Results table with ResultTime, Balance, Equity which is updated with a new row every 5 minutes. I've used SUMX to find opening and closing balances and it has worked so far.
Res_OpeningBalance:=SUMX(TOPN(1,Results,Results[ResultTime],1),[Balance])
Res_ClosingBalance:=SUMX(TOPN(1,Results,Results[ResultTime],0),[Balance])
But when I tried it with dates, the whole thing fell apart.
Res_MaxBalance_Date:=SUMX(TOPN(1,Results,Results[Balance],0),[ResultTime])
Since the highest Balance is likely to be represented through many rows due to it lasting more than 5 minutes, ResultTime (which is unique to each row) is summed up and returns messed up dates well into the future. How to return only one date (first or last
datetime) from the rows where Balance is at max?
I tried a TOPN of TOPN, but Excel was not amused.
=SUMX(TOPN(1,Results,Results[Balance],0),TOPN(1,Results,Results[ResultTime],0))
TIA!
Re
Dennis

Answer 1

I still don't understand RANKX, but I figured it out anyway. I get the correct data by using:
Res_MaxBalance:=MAX(Results[Balance])
Res_MaxBalanceDate:=CALCULATE(MAX(Results[ResultTime]),FILTER(Results, Results[Balance]=MAX(Results[Balance])))
Res_MinBalance:=MIN(Results[Balance])
Res_MinBalanceDate:=CALCULATE(MAX(Results[ResultTime]),FILTER(Results, Results[Balance]=MIN(Results[Balance])))
Res_MaxEquity:=MAX(Results[Equity])
Res_MaxEquityDate:=CALCULATE(MAX(Results[ResultTime]),FILTER(Results, Results[Equity]=MAX(Results[Equity])))
Res_MinEquity:=MIN(Results[Equity])
Res_MinEquityDate:=CALCULATE(MAX(Results[ResultTime]),FILTER(Results, Results[Equity]=MIN(Results[Equity])))
Re
D