How to calculate monthly total at the end of every month in php?

I have the following code which
queries a database and presents the
results:

<?php



include('connect.php');



$query="SELECT date1,day(date1) as month1,year(date1)as month2,(month( date1 ) - month(date1 )) as difference,SUM(gtotal) AS daily_total,COUNT(id) AS num_orders FROM `sale` where date1>='2012-01-28' AND date1<='2013-02-28' and tax_name='C.S.T. 4% ON SCRAP' and tin='Applied For' GROUP BY month(date1), day(date1), id ";





$qt=mysql_query($query);

echo mysql_error();

echo "<table border='1' cellspacing='1' cellpadding='0' width='400'>

<tr valign='top' bgcolor=#363636 style='color:#ffffff;'>

<td ><b>No. of orders</b></td>

<td><b>Date</b></td>

<td><b>Month<br>(dt)</b></td>

<td><b>Year<br>(dt2)</b></td>

<td><b>Daily Sale</b></td></tr>";

while($nt=mysql_fetch_array($qt)){

echo "<tr valign='top'> <td><font face='Verdana' size='2' >$nt[num_orders]</font></td>

<td><font face='Verdana' size='2' >$nt[date1]</font></td>

<td><font face='Verdana' size='2' >$nt[month1]</font></td>

<td><font face='Verdana' size='2' >$nt[month2]</font></td>

<td><font face='Verdana' size='2' ><?php echo $nt[gtotal];?></font></td></tr>";





echo "<tr bgcolor=#c2c2c2><td colspan=3></td><td ><b>Daily Total</b></td><td>$nt[daily_total]</td><…



echo "<tr valign='top'><td colspan=5></td></tr>";



$query1="SELECT * FROM `sale` where date1>='2012-01-28' AND date1<='2013-01-31' and tax_name='C.S.T. 4% ON SCRAP' and tin='Applied For' and gtotal ";



$qt1=mysql_query($query1);

echo mysql_error();

$num=mysql_num_rows($qt1);

if($num)

{

$p=0;

$q=0;



while($nt1=mysql_fetch_array($qt1)){



$p=$p+$nt1['gtotal'];

$q=$q+$nt1['subtotal'];}}

echo "<tr valign='top' bgcolor=#c6c6c6>

<td><font face='Verdana' size='2' >$C</font></td>

<td><font face='Verdana' size='2' ><b>subtotal<br></b></font></td>

<td><font face='Verdana' size='2' >$q</font></td>

<td><font face='Verdana' size='2' ><b>gtotal<br></b></font></td>

<td><font face='Verdana' size='2' >$p</td></tr>";



echo "</table>";

?>

It shows daily total
But I have hundreds of data items to
calculate. Suppose I have 5 data items
in January, they all should be seen in 5
rows and at the end of month there
should be the month total and so on
until 12 months. Please help