Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
Year | Production | Unit of Measure | % Change |
2002 | 2369400 | Metric tons, gross weight | NA |
2003 | 2927500 | Metric tons, gross weight | 23.55% |
2004 | 3287100 | Metric tons, gross weight | 12.28% |
2005 | 3581242 | Metric tons, gross weight | 8.95% |
2006 | 3366078 | Metric tons, gross weight | -6.01% |
2007 | 3687200 | Metric tons, gross weight | 9.54% |
2008 | 3552000 | Metric tons, gross weight | -3.67% |
2009 | 3544000 | Metric tons, gross weight | -0.23% |
2010 | 3760000 | Metric tons, gross weight | 6.09% |
2011 | 3800000 | Metric tons, gross weight | 1.06% |
2012 | 4000000 | Metric tons, gross weight | 5.26% |