Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 13057 | Metric tons | NA |
| 2004 | 13063 | Metric tons | 0.05% |
| 2005 | 1000 | Metric tons | -92.34% |
| 2006 | 11054 | Metric tons | 1,005.40% |
| 2007 | 9800 | Metric tons | -11.34% |
| 2008 | 10000 | Metric tons | 2.04% |
