Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 3.09999990463257 | Thousand metric tons | NA |
| 2004 | 19.1000003814697 | Thousand metric tons | 516.13% |
| 2005 | 7.30000019073486 | Thousand metric tons | -61.78% |
| 2006 | 11.3000001907349 | Thousand metric tons | 54.79% |
| 2007 | 17.6000003814697 | Thousand metric tons | 55.75% |
| 2008 | 28.1000003814697 | Thousand metric tons | 59.66% |
| 2010 | 57.7999992370605 | Thousand metric tons | 105.69% |
| 2011 | 214.300003051758 | Thousand metric tons | 270.76% |
| 2012 | 230 | Thousand metric tons | 7.33% |
