change format of decimal not working

hi guys,
can you please look into my code and advise me why i can't change my value from 1000 to 1,000.00
Dim y As Decimal() = New Decimal(DT.Rows.Count - 1) {} For i As Integer = 0 To DT.Rows.Count - 1 y(i) = Format(CDbl(DT.Rows(i).Item("total")), "##,0.00") Next