Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 196169 | Metric tons | NA |
| 2004 | 275607 | Metric tons | 40.49 % |
| 2005 | 231184 | Metric tons | -16.12 % |
| 2006 | 246000 | Metric tons | 6.41 % |
| 2007 | 249495 | Metric tons | 1.42 % |
| 2008 | 296000 | Metric tons | 18.64 % |
| 2009 | 200000 | Metric tons | -32.43 % |
