Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 20 | Metric tons | NA |
| 2003 | 22 | Metric tons | 10.00 % |
| 2004 | 24 | Metric tons | 9.09 % |
| 2005 | 23.7859992980957 | Metric tons | -0.89 % |
| 2006 | 20.076000213623 | Metric tons | -15.60 % |
| 2007 | 24.1669998168945 | Metric tons | 20.38 % |
| 2008 | 24 | Metric tons | -0.69 % |
