<form name="loandata">
    <table>
      <tr><td><b>enter loan information:</b></td></tr>
      <tr>
        <td>1) amount of the loan (any currency):</td>
        <td><input type="text" name="principal" onchange="calculate();"></td>
      </tr>
      <tr>
        <td>2) annual percentage rate of interest:</td>
        <td><input type="text" name="interest" onchange="calculate();"></td>
      </tr>
      <tr>
        <td>3) repayment period in years:</td>
        <td><input type="text" name="years" onchange="calculate();"></td>
      </tr>
      <tr><td></td>
        <td><input type="button" value="compute" onclick="calculate();"></td>
      </tr>
      <tr><td><b>payment information:</b></td></tr>
      <tr>
        <td>4) your monthly payment:</td>
        <td>$$<span class="result" id="payment"></span></td>
      </tr>
      <tr>
        <td>5) your total payment:</td>
        <td><span class="result" id="total"></span></td>
      </tr>
      <tr>
        <td>6) your total interest payments:</td>
        <td>$$<span class="result" id="totalinterest"></span></td>
      </tr>
    </table>
  </form>