The 2007 national census reported a total population for this woreda of 141,426, of whom 70,787 were men and 70,639 were women; 10,531 or 14.89% of its population were urban dwellers. The majority of the inhabitants said they practised Ethiopian Orthodox Christianity, with 64.87% of the population reporting they practised that belief, and 34.92% were Muslim.[2]
Based on figures published by the Central Statistical Agency in 2005, this woreda has an estimated total population of 193,214, of whom 99,085 are men and 94,129 are women; 5,719 or 2.96% of its population are urban dwellers, which is less than the Zone average of 9.5%. With an estimated area of 1,550.47 square kilometers, Dera has an estimated population density of 124.6 people per square kilometer, which is less than the Zone average of 143.[3]
The 1994 national census reported a total population for this woreda of 139,661, of whom 68,474 were men and 71,187 women; 3,210 or 2.3% of its population were urban dwellers at the time. Dera is almost evenly divided between the two largest ethnic groups reported in this woreda: the Oromo (50.18%), and the Amhara (49.76%). Further, Amharic was spoken as a first language by 50.69%, and 49.28% spoke Oromo. The majority of the inhabitants professed Ethiopian Orthodox Christianity, with 64.49% of the population reporting they practiced that belief, while 35.45% of the population said they were Muslim.[4]