Please can you help me shorten this formula
The desired result is the TOTAL SUM of the values from spreadsheet 'Month (1)" columns (C8:C400)+(F8:F400)+(I8:I400)+(L8:L400)+(08:O400)
IF(C8="","",SUMIFS('Month (1)'!C$8:C$400,'Month (1)'!B$8:B$400,C8))
+IF(C8="","",SUMIFS('Month...