thanks but i dont have access to any back end functionality to create these additional dimensions - only have access to the front end reporting tool

thanks for all the suggestions - got it to work using formula below then filtering for first rows only rcount( "Appointment (details)"."Pre-op date/time" by "Patient"."Medical record number" )

thanks for suggestion re variables but in the end just used below as filter: First day of previous month TIMESTAMPADD(SQL_TSI_MONTH, -1, TIMESTAMPADD( SQL_TSI_DAY , DAYOFMONTH( CURRENT_DATE) * -(1) + 1, CURRENT_DATE)) Last day of previous month TIMESTAMPADD( SQL_TSI_DAY , -(1), TIMESTAMPADD( SQL_TSI_DAY , DAYOFMONTH(…