Why Printer is printing more blank page below the content..?

See more:

C#

ASP.NET

I have a page for bill printing ..i m printing whole page content through javascript func.. It is printing well whole content..

BUT IT LEAVES MUCH BLANK PAGE BELOW..

Following are javascript print fun which i use.. i m calling this fun on button click..
PrintArea is id of panel

<script type="text/javascript">
    


function CallPrint() {
        var res = document.getElementById('<%=PrintArea.ClientID%>');
        var contentFormat = "<style>td{font-family:verdana;font-size:10px}th{font-family:verdana;font-size:11px;font-weight:bold}</style><table width=\"100%\" cellpadding=\"0\" cellspacing=\"0\"><tr><td align=\"center\" valign=\"top\" style=\"font-family:verdana; font-size:14px; font-weight:normal\">" + "</td></tr><tr><td align=\"left\" valign=\"top\" style=\"font-family:verdana; font-size:12px;height:24px; font-weight:normal\"> " + "</td></tr><tr><td align=\"left\" valign=\"top\"><br />" + res.innerHTML + "</td></tr></table>"
        var WinPrint = window.open('', '', 'scrollbars,left=0,top=0,width=500,height=600,status=0');
        WinPrint.document.write(contentFormat);
        WinPrint.document.close();
        WinPrint.focus();
        WinPrint.print();
    }
</script>