Dim q = From row As DataRow In dt
         Let wk As Integer =
            cal.GetWeekOfYear(row.Field(Of Date)("Eintrag"),
            Globalization.CalendarWeekRule.FirstFourDayWeek,
            DayOfWeek.Monday)
         Let Minuten = row.Field(Of Integer)("Stoerdauer")
         Let Instandhaltung = row.Field(Of String)("Eintrag-Instandhaltung")
         Where year = row.Field(Of Date)("Eintrag").Year _
             AndAlso wk = week _
             AndAlso row.Field(Of Integer)("MaschID") = masch _
             AndAlso row.Field(Of String)("Eintrag-Instandhaltung") <> Text
         Group By art = Instandhaltung, Minuten Into Count()