Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 373 | Thousand metric tons | NA |
| 2003 | 466 | Thousand metric tons | 24.93% |
| 2004 | 83 | Thousand metric tons | -82.19% |
