Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2009 | 17.5137004852295 | Thousand metric tons | NA |
| 2012 | 1.43900001049042 | Thousand metric tons | -91.78% |
| 2013 | 1.5 | Thousand metric tons | 4.24% |
