Decatur, AR has a population of 2,272 and is the 10,331st largest city in the United States. The population density is 508 per sq mi which is 816% higher than the Arkansas average and 461% higher than the national average. The median age in Decatur is 27 which is approximately 29% lower than the Arkansas average of 38. In Decatur, 57% of the population over 15 years of age are married, 52% speak English and 42% speak Spanish. 42% of Decatur residents were born in Arkansas, 32% were born out of state, 1% were born outside of the United States and 25% were foreign born.