Help with this measure......MAX DATE BY LOCATION

[jackmccarthy]

This measure was written LASTNONBLANK('TRANSACTION TABLE ADEPT'[datetimestamp], CALCULATE(COUNTROWS('TRANSACTION TABLE ADEPT'), 'TRANSACTION TABLE ADEPT'[activity]=9,))It works great, However I need to return the max date for each location I have. Can someone show me how I might do this?