Distinc count Active Customer from Historical Table by Month

[CHINH]

Hi everyone

I've been looking around the community for something that might provide an answer to my problem. I have a Table hitorical Customer which display as below and I want to distinc Count Customer_Code by each month. 

I tried create measure as below but didnot work

= TOTALYTD(COUNTDISTINC(CUSTOMER_HISTORY[CUSTOMER_CODE])),'DATE'[Date])

Thanks for your attentions. And appriciate to guide me to solve.

[Jihwan_Kim · Accepted solution]

Hi,

I am not sure how your datemodel looks like, but I tried to create a sample pbix file like below.
Please check the below picture and the attached pbix file.

I hope the below can provide some ideas on how to create a solution for your datamodel.

Customer Count measure: =
VAR _t =
    SUMMARIZE (
        FILTER (
            CUSTOMER_HISTORY,
            CUSTOMER_HISTORY[FROM_DATE] <= MAX ( 'Date'[Date] )
                && OR (
                    CUSTOMER_HISTORY[TO_DATE] >= MIN ( 'Date'[Date] ),
                    CUSTOMER_HISTORY[TO_DATE] = BLANK ()
                )
        ),
        CUSTOMER_HISTORY[CUSTOMER_CODE]
    )
RETURN
    COUNTROWS ( _t )

[CHINH]

Dear Jihwan_Kim

By refer to your solution, I worked with me, thanks