Spencer is located in northwest Iowa. Spencer is part of Clay County. Spencer has 11.01 square miles of land area and 0.16 square miles of water area. As of 2010-2014, the total Spencer population is 11,177, which has shrunk 1.24% since 2000. The population growth rate is much lower than the state average rate of 5.19% and is much lower than the national average rate of 11.61%. Spencer median household income is $44,467 in 2010-2014 and has grown by 34.87% since 2000. The income growth rate is about the same as the state average rate of 33.56% and is higher than the national average rate of 27.36%. Spencer median house value is $110,300 in 2010-2014 and has grown by 36.34% since 2000. The house value growth rate is lower than the state average rate of 53.09% 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 Spencer is much better than the state average in quality. The Spencer area code is 712.