| Year | Population |
| 2000 | 3,254,821 |
| 2001 | 3,378,073 |
| 2002 | 3,486,831 |
| 2003 | 3,617,130 |
| 2004 | 3,753,081 |
| 2005 | 3,871,591 |
| 2006 | 3,982,512 |
| 2007 | 4,066,573 |
| 2008 | 4,115,871 |
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“Inland Empire” defined as the Riverside-San Bernardino-Ontario Metropolitan Statistical Area. Census data for 2000; 2001-2008 are Census Bureau estimates.