用for循环怎么改变利率，计算利率分别为5%，6%,7%,8%,9%,10%。为JTextArea增加滚动功能。求解

Question

package chp1;

import java.text.NumberFormat; 

import java.util.Locale;  

import javax.swing.JOptionPane;

import javax.swing.JTextArea;

public class Interest {

   public static void main( String args[] )

   {

      double amount;     

      double principal = 1000.0;  

      double rate = 0.05;         

      NumberFormat moneyFormat = 

         NumberFormat.getCurrencyInstance( Locale.US );

      JTextArea outputTextArea = new JTextArea();

      outputTextArea.setText( "Year\tAmount on deposit\n" );

      for ( int year = 1; year <= 10; year++ ) {

         amount = principal * Math.pow( 1.0 + rate, year );

         outputTextArea.append( year + "\t" +

            moneyFormat.format( amount ) + "\n" );

      } 

      JOptionPane.showMessageDialog( null, outputTextArea,

         "Compound Interest", JOptionPane.INFORMATION_MESSAGE );

      System.exit( 0 ); 

   } 

}