DAX for Calculating Moving Average

Hi djkoenig 

For the questions you raised, here are the solutions I offered:

I used the data you provided

“data”

“Date”

Create a measure to find La2O3(g/L) within 30 days

MA 30(La2O3) = var max_date = MAX('Date'[Date])
var _la2o3 = CALCULATE(max('data'[La2O3 (g/L)]), FILTER(ALL('data'), [Cell] = MAX('data'[Cell]) && 'data'[La2O3 (g/L)] = MAX('data'[La2O3 (g/L)]) && [Date] > EDATE(max_date, -1) ))
RETURN _la2o3 

Calculate the average of MA 30 (La2O3).

MA 30 (La2O3)_avg = var max_date = MAX('Date'[Date])
var _la2o3_avg = CALCULATE(AVERAGE('data'[La2O3 (g/L)]), FILTER(ALL('data'), [Cell] = MAX('data'[Cell]) && [Date] > EDATE(max_date, -1) ))
RETURN  _la2o3_avg

If you want to remove blank rows from MA 30 (La2O3), you can do the following: you can apply "is not blank" to MA 30 (La2O3) in the Filters

Here is the result:

result = var max_date = MAX('Date'[Date])
var _la2o3 = CALCULATE(max('data'[La2O3 (g/L)]), FILTER(ALL('data'), [Cell] = MAX('data'[Cell]) && 'data'[La2O3 (g/L)] = MAX('data'[La2O3 (g/L)]) && [Date] > EDATE(max_date, -1) ))
var _la2o3_avg = CALCULATE(AVERAGE('data'[La2O3 (g/L)]), FILTER(ALL('data'), [Cell] = MAX('data'[Cell]) && [Date] > EDATE(max_date, -1) ))
RETURN  _la2o3 - _la2o3_avg

Best Regards,

Nono Chen

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