MessageBox.Show(dp.XValue + "," + dp.YValues[0]);
        }
    }

System.Windows.Forms.DataVisualization.Charting.DataPoint dp = new System.Windows.Forms.DataVisualization.Charting.DataPoint();
            dp.SetValueXY(d["year"] + "年" + d["month"] + "月" + d["day"] + "日", int.Parse(d["sheets"]));  //XとYの値を設定
            dp.IsValueShownAsLabel = true;
            this.series2.Points.Add(dp);
        }