Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
Year | Production | Unit of Measure | % Change |
2003 | 28000 | Metric tons | NA |
2004 | 28000 | Metric tons | 0.00 % |
2005 | 29000 | Metric tons | 3.57 % |
2006 | 28000 | Metric tons | -3.45 % |
2007 | 28000 | Metric tons | 0.00 % |
2008 | 28000 | Metric tons | 0.00 % |
2009 | 28000 | Metric tons | 0.00 % |
2010 | 26000 | Metric tons | -7.14 % |
2011 | 25000 | Metric tons | -3.85 % |
2012 | 20000 | Metric tons | -20.00 % |
2013 | 22000 | Metric tons | 10.00 % |