Mining is the biggest contributor to Namibia's economy in terms of revenue. It accounts for 25% of the country's income. Its contribution to the gross domestic product (10.4% in 2009, 8.5% in 2010, 9.5% in 2011, 12.3% in 2012, 13.2% in 2013, 11.6% in 2014) is also very important and makes it one of the largest economic sectors of the country. The majority of revenue (7.2% of GDP in 2011) comes from diamond mining.