Now you're digging into ancient history - I note that I stuffed up the code in the original answer too...
Instead:
<?php if ($feed_row->getField('chg_today_fm') < 0) { $style = " style=\"color: red\""; } else { $style = ""; } ?>
<p <?php echo $style; ?>><?php echo "$" .number_format($feed_row->getField('chg_today_fm'), 2, '.', ','); ?></p>
Cheers
Webko