In an attempt to reduce junk food consumption through price control, forms of Pigovian taxation have been implemented. Targeting saturated fat consumption, Denmark introduced the world's first fat-food tax in October, 2011, by imposing a surcharge on all foods, including those made from natural ingredients, that contain more than percent saturated fat, an unpopular measure that lasted a little over a year.    Hungary has also imposed a tax on packaged foods that contain unhealthy concentrations, such as beverages containing more than 20 mg of caffeine per 100 ml.  Norway taxes refined sugar, and Mexico has various excises on unhealthy food.  On April 1, 2015, the first fat tax in the US, the Navajo Nation 's Healthy Diné Nation Act of 2014, mandating a 2% junk food tax, came into effect, covering the 27,000 sq. mi. of Navajo reservation; the Act targeted problems with obesity and diabetes among the Navajo population.