private void drawStrings(Graphics g) {
        g.setColor(stringColor);
        g.setFont(new Font("Courier", Font.PLAIN, 12));
        g.drawString("Birthday : " + yourBiorhythm.getBirthdayYear() +
                     "/" + yourBiorhythm.getBirthdayMonth() +
                     "/" + yourBiorhythm.getBirthdayDate(), 0, 12);
        g.drawString("Calculate day : ", 135, 208);
        g.setFont(new Font("Dialog", Font.PLAIN, 24));
        g.drawString(yourBiorhythm.getCalcYear() + "/" +
                     yourBiorhythm.getCalcMonth() + "/" +
                     yourBiorhythm.getCalcDate(),
                         245, 208);
    }