Although cereal and vegetable output dropped by 40% between 1990 and 2008, output in grains has since increased, and the 2016–2017 season registered the biggest grain output in a decade. Maize, barley, oats and rice are also grown. Quality Oriental tobacco is a significant industrial crop. Bulgaria is also the largest producer globally of lavender and rose oil, both widely used in fragrances. Within the services sector, tourism is a significant contributor to economic growth. Sofia, Plovdiv, Veliko Tarnovo, coastal resorts Albena, Golden Sands and Sunny Beach and winter resorts Bansko, Pamporovo and Borovets are some of the locations most visited by tourists. Most visitors are Romanian, Turkish, Greek and German. Tourism is additionally encouraged through the 100 Tourist Sites system.