How to convert working New Table DAX to addcolumns DAX

[TheKiltedGolfer]

I created a “New Table” by clicking on the “Modeling” tab and selecting “New Table.”  I then entered the following DAX, which works with NO issues at all.

LatestFilerGap%Table = ADDCOLUMNS('Filer Capacity', "Latest Filer Gap%", 1-LOOKUPVALUE('Filer Capacity'[Gap%], [date], MAX('Filer Capacity'[date])))

However, this adds a whole new table and increases the size to my overall report, which I would like to reduce.  What I really want is to just execute the same “ADDCOLUMNS” DAX formula to my existing ‘Filer Capacity” table but it DOES NOT work.  I have no idea why it does not. If I can create a whole new table why can’t I just add the same information to the existing table“Filer Capacity?”  I want to add column “Latest Filer Gap%” to my existing table “Filer Capacity.”  Any solutions?  I thought this would be straight forward but I cannot figure it out. Or is the way that I made it work, by creating a whole new table based on my existing “Filer Capacity” table, the only way to go?

[Greg_Deckler · Accepted solution]

So you are saying that this in a calculated column does not work?

1-LOOKUPVALUE('Filer Capacity'[Gap%], [date], MAX('Filer Capacity'[date]))

Do you get an error or just the wrong value?

[TheKiltedGolfer]

As usual, this is what I get for over complicating things.  I tried to use the ADDCOLUMNS, from the DAX that worked, when adding a column to a table that already exists. Sort of double adding a column?  LOL  Thank you very much for your quick response and answer.