Hong Kong produces millions of tons of solid waste each year, including billions of plastic shopping bags. Plastic bags are not biodegradable and occupy landfill space. The government implemented an environmental levy scheme on plastic shopping bags in 2009 to encourage reuse and reduce plastic bag usage. The scheme charges retailers 50 cents for each plastic bag distributed, which they must record and remit quarterly to the government. It was later expanded in 2011 to include small and medium retailers. The levy scheme successfully created an economic incentive for consumers to switch to reusable bags and reduced plastic bag usage.