This is a bar graph showing the notification rate (per 100,000 population) for Ross River virus notifications from the Perth Metropolitan and Peel regions in the off-season (June to September inclusive) for the years 2002 to 2011. It shows an increase in the notification rate for the years 2006 to 2009 inclusive up to a peak of 57 notifications per 100,000 population from the Peel region in 2008.