The nearly 10% sales increase posted by HarperCollins in fiscal 2004 helped to boost revenue 24% at the publisher between fiscal 2000 and 2004. Operating income increased at a much more dramatic rate, jumping 77.5% in the five-year period. The big gains in operating income resulted in a steady increase in operating margins over the years. HC operating margin was 8.9% in fiscal 2000, and rose every year between fiscal 2000 and 2004, when it reached 12.4%.