age from mysql

   <tr>    <td align="right"><font color="blue"><b>Age</b></font>:</td>    <td>     <b><?   $dob_r = explode('-', $user_data['dob']);   $curr_time = time();   $birth_time = mktime(0, 0, 0, $dob_r[1], $dob_r[2], $dob_r[0]);   $diff_time = $curr_time - $birth_time;   echo strftime('%Y', $diff_time) - (strftime('%Y', 0));?>     </b>    </td>   </tr>