How to create a calculated column with cumulative count?

Syndicate_Admin 

Are you adding a cummulative column in the table "ROSAinfo" or a different one?
Based on which column in which table do want to added cummulative column ?

It seems like the formula you've provided is attempting to count the occurrences of a specific value in a column, but with the additional condition that it's the first time the value appears in the column based on the minimum install date.

However, the formula you've provided may not be returning any values because the condition in the filter function is looking for rows where the Zimmer Acct # and Install Date are both equal to the selected value and the minimum install date, respectively. This may not always be true, especially if there are multiple rows with the same Zimmer Acct # and Install Date.

To accumulate the count of occurrences of a value in a column, you can use the RANKX function in Power BI. The RANKX function assigns a rank to each value in a column based on a specified expression, and you can use this rank to determine the number of times a value has appeared.

Here's an example of how you can modify your formula to use the RANKX function:

Count1 = VAR SelectedZimmerAcct = SELECTEDVALUE(ROSAinfo[Zimmer Acct #]) RETURN RANKX( FILTER( ALL(ROSAinfo), ROSAinfo[Zimmer Acct #] = SelectedZimmerAcct ), MIN(ROSAinfo[Install Date]) )

In this formula, we first store the selected Zimmer Acct # in a variable. Then, we use the FILTER function to return a table of all the rows in the ROSAinfo table where the Zimmer Acct # matches the selected value. We then use the RANKX function to assign a rank to each row based on the minimum install date. This rank represents the number of times the Zimmer Acct # has appeared in the table up to that point. Finally, we return this rank as the output of the measure.

Note that this formula assumes that the Install Date column contains dates in a format that Power BI can recognize as such. If your Install Date column is not recognized as a date, you may need to convert it using the DATE function.

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