<?php

$sku = nl2br($_product->getSku());
$_productCollection = Mage::getResourceModel('reports/product_collection')
->addOrderedQty()
->addAttributeToFilter('sku', $sku)
->setOrder('ordered_qty', 'desc')
->getFirstItem();
$product = $_productCollection;
echo '<span style="font-size:12px;color:#333;font-weight:100;">Orders('.(int)$product->ordered_qty .')</span>';

?>