First let me introduce an example:
I have a table of raw scores for players each day, it's call "Raw Score".
I also have this table of modifiers that I will apply to each players' daily raw score, it's called "ScoreMod".
I also have this table that calculates their total effective scores. It's called "Total".
To calculate each player's daily effective score (raw scores + modifiers), I use the following function.
=LET(
MyDate, FILTER(RawScore[Date],RawScore[Name]=Total[@Name]),
MyRawScore,FILTER(RawScore[Score],RawScore[Name]=Total[@Name]),
MyModifier,XLOOKUP(
MyDate,
FILTER(ScoreMod[Date], ScoreMod[Name]=Total[@Name],0),
FILTER(ScoreMod[Modifier], ScoreMod[Name]=Total[@Name],0), 0),
MyModifier + MyRawScore)
This function works just fine, as show in the picture. Tom's effective scores are correctly calculated.
Then I define the above function as EffectiveScore.
However, when I try to use =SUM(EffectiveScore) for Tom's total score in the Total table, the result is incorrect, as it becomes 300.
But if I use =SUM(+EffectiveScore) for Tom's total score, then the result is the correct total score, 280.
My question is, why the formula without the + can not get me the correct answer, and why adding a + gets me the right answer?
Link to the document: https://1drv.ms/x/s!At1ltp8PtMK-gpsP2cOPZStP89ozpw



