Ok - I optimized a little:
DateDiff('h',Sum([tbl_log].[Off Time]),Sum([tbl_log].[On Time])) AS Hours,DateDiff('n',Sum([tbl_log].[Off Time]),Sum([tbl_log].[On Time])) AS Minutes,DateDiff('s',Sum([tbl_log].[Off Time]),Sum([tbl_log].[On Time])) - DateDiff('n',Sum([tbl_log].[Off...