The practice then should be to put a range of years encompassing all updates, e.g., 2009-2013. If you didn't touch the site in a certain year, you'd include a l

The practice then should be to put a range of years encompassing all updates, e.g., 2009-2013. If you didn't touch the site in a certain year, you'd include a list of ranges and/or specific years, e.g., 2007, 2009, 2011-2013