Source: United States Geological Survey (USGS) Minerals Resources Program
Note: Check source table for details and footnotes
| Year | Production | Unit of Measure | % Change |
| 2003 | 1742.59997558594 | Thousand metric tons of contained nitrogen | NA |
| 2004 | 1726.19995117188 | Thousand metric tons of contained nitrogen | -0.94% |
| 2005 | 1780 | Thousand metric tons of contained nitrogen | 3.12% |
| 2006 | 2000 | Thousand metric tons of contained nitrogen | 12.36% |
| 2007 | 2600 | Thousand metric tons of contained nitrogen | 30.00% |
| 2008 | 2500 | Thousand metric tons of contained nitrogen | -3.85% |
| 2009 | 2400 | Thousand metric tons of contained nitrogen | -4.00% |
| 2010 | 2500 | Thousand metric tons of contained nitrogen | 4.17% |
| 2011 | 2800 | Thousand metric tons of contained nitrogen | 12.00% |
| 2012 | 3700 | Thousand metric tons of contained nitrogen | 32.14% |
