Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 11290 | Metric tons | NA |
| 2004 | 6316 | Metric tons | -44.06 % |
| 2005 | 15671 | Metric tons | 148.12 % |
| 2006 | 23773 | Metric tons | 51.70 % |
| 2007 | 24000 | Metric tons | 0.95 % |
| 2008 | 25000 | Metric tons | 4.17 % |
| 2009 | 26000 | Metric tons | 4.00 % |
