private void gridView1_CustomDrawFooterCell(object sender, DevExpress.XtraGrid.Views.Grid.FooterCellCustomDrawEventArgs e) {
            try {

                if (e.Column == GR_GECIKMIS_ALACAK_YUZDESI) {
                    double BAKIYE = double.Parse(gridView1.Columns["BAKIYE"].SummaryItem.SummaryValue.ToString());
                    double TUTAR = double.Parse(gridView1.Columns["TUTAR"].SummaryItem.SummaryValue.ToString());
                    double YORAN = Math.Round( (BAKIYE / TUTAR)*100,2);
                    GridView view = (GridView)sender;
                    e.Info.DisplayText ="%"+ YORAN.ToString();
                }

            } catch {

            }
        }