dynamic copyright in page footer?

Hello, I am trying to use php to put a copyright notice in a page footer. I'm using the date function with the "Y" value for the year. Here's the code: <?php echo date ('Y'); ?> This works great for a site done in 2011 but next year I'm going to want to have 2011 and 2012 in the copyright notice, adding an additional year the site's up. I'd appreciate some suggestions i'm very likely overthinking this. Thanks. Dave.