Monmouth is located in west Oregon. Monmouth is between the Polk, Benton county. Monmouth has 2.24 square miles of land area and has no water area. As of 2010-2014, the total Monmouth population is 9,769, which has grown 26.20% since 2000. The population growth rate is much higher than the state average rate of 14.00% and is much higher than the national average rate of 11.61%. Monmouth median household income is $35,750 in 2010-2014 and has grown by 10.83% since 2000. The income growth rate is much lower than the state average rate of 23.47% and is much lower than the national average rate of 27.36%. Monmouth median house value is $188,500 in 2010-2014 and has grown by 37.29% since 2000. The house value growth rate is lower than the state average rate of 53.91% and is lower than the national average rate of 46.91%. As a reference, the national Consumer Price Index (CPI) inflation rate for the same period is 26.63%. On average, the public school district that covers Monmouth is worse than the state average in quality. The Monmouth area code is 503.