tablix countrow ??

Hi,I have a report using a tablix with a row with uses child column with expression =countdistinct(Fields!DayofMonth.Value) puts a 1 in the coulmn if it has a valueI want to sum it up at the bottom of the column at the end of the report I think I should use a countrow command ?hope this is enough info to get some ideas or where to look..ThanksJoe