Not incremented tabindex

foreach (string item in valueslist)
                        {
                            TableRow tr = new TableRow();
                            TableCell tc = new TableCell();
                            TableCell col2 = new TableCell();

                            Label lb = new Label();
                            lb.Text = item;

                            TextBox tb1 = new TextBox();
                            tb1.Style["text-align"] = "Right";
                            
                            tb1.ID = "txt" + k;
                            tb1.Text = "0";

                            tb1.EnableViewState = true;
                            tb1.AutoPostBack = true;
                            tb1.TextChanged += new EventHandler(tb1_TextChanged);

                            int cnt = 0;
                            tb1.ID = "Tab" + cnt.ToString();//Not incremented tabindex
                            tb1.TabIndex = (short)(cnt);
                            cnt++; 
                            

                            tb1.Text = "0";
                            string ids = string.Format("lb{0}", k);
                            lb.ID = ids;
                            tc.Controls.Add(lb);
                            col2.Controls.Add(tb1);

                            tr.Controls.Add(tc);
                            tr.Controls.Add(col2);

                            table.Controls.Add(tr);

                            k++;

                        }