private void YearBoxActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_YearBoxActionPerformed
       int m = MonthBox.getSelectedIndex() + 1;
                    int y = YearBox.getSelectedIndex() + (Calendar.getInstance().get(Calendar.YEAR) - CountYears);
                    int n = m != 2 ? m > 7 ? 30 + m % 2 == 1 ? 0 : 1 : 30 + m % 2 : y % 4 == 0 && y % 100 != 0 || y % 400 == 0 ? 29 : 28;
                    Integer[] Days = new Integer[n];
                    for (int i = 1; i < n + 1; i++) {
                        Days[i - 1] = i;
                    }
                    DayBox.setModel(new DefaultComboBoxModel(Days));
    }//GEN-LAST:event_YearBoxActionPerformed