Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
Year | Production | Unit of Measure | % Change |
2003 | 31779 | Thousand metric tons | NA |
2004 | 32600 | Thousand metric tons | 2.58% |
2005 | 45800 | Thousand metric tons | 40.49% |
2006 | 49500 | Thousand metric tons | 8.08% |
2007 | 53100 | Thousand metric tons | 7.27% |