Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2002 | 84236.3984375 | Thousand metric tons | NA |
| 2003 | 91759.796875 | Thousand metric tons | 8.93 % |
| 2004 | 96980 | Thousand metric tons | 5.69 % |
| 2005 | 96764.3984375 | Thousand metric tons | -0.22 % |
| 2006 | 102000 | Thousand metric tons | 5.41 % |
| 2007 | 105000 | Thousand metric tons | 2.94 % |
| 2008 | 99900 | Thousand metric tons | -4.86 % |
| 2009 | 92000 | Thousand metric tons | -7.91 % |