I have a Table A with a time field and a "value" field, with a lot of records, and a Table B with 3 records, where I want to store the average of the table A values during last month (M-1), M-2 and M-3, as well as the standard deviation for each month, and the percentage of records that are 1*sigma away from the average for each month. I related Table A with Table B by the month number and I managed to get the standard deviation of Table A::value for each month by stdev function. But how can I calculate the % of records 1*sigma away from the average?

I tried to add a field of calculation in table A which is abs(Table A::value - Table B::average), but it doesn't get any result. Maybe because the Table B:average is already a calculation of Table A related to Table B, so it can't be used in Table A?

Hope to get answer here. Thanks in advance.

Shouldn't matter where the data for the calculation comes from.

Have a look into the attached file.