multiple sql query with loop and some time interval

SqlConnection sqlconn = new SqlConnection(str);
            sqlconn.Open();
            string strquery;
            strquery = "SELECT Indices_id, IndicesName, LastPrice, ChangePrice * .63 AS 'change of price', Percentage FROM Table1";
            strquery2 = "SELECT Indices_id, IndicesName, LastPrice, ChangePrice * .60 AS 'change of price', Percentage FROM Table1";
            strquery3 = "SELECT Indices_id, IndicesName, LastPrice, ChangePrice * -.60 AS 'change of price', Percentage FROM Table1";
            SqlCommand sqlcmd = new SqlCommand(strquery, sqlconn);
            DataSet ds = new DataSet();
            SqlDataAdapter sda = new SqlDataAdapter();
            sda.SelectCommand = sqlcmd;
            sda.Fill(ds);
            GridView1.DataSource = ds;
            GridView1.DataBind();