Based on the 2007 Census conducted by the Central Statistical Agency of Ethiopia (CSA), this Zone has a total population of 1,350,415, of whom 671,538 are men and 678,877 women; with an area of 10,833.19 square kilometers, West Welega has a population density of 124.66. While 146,672 or 7.39% are urban inhabitants, a further 2,578 or 0.19% are pastoralists. A total of 266,773 households were counted in this Zone, which results in an average of 5.06 persons to a household, and 250,473 housing units. The three largest ethnic groups reported in West Welega were the Oromo (76.72%), the Mao (1.45%), and the Amhara (21.2%); all other ethnic groups made up 0.63% of the population. Oromo was spoken as a first language by 97.06%, 1.36% spoke Mao, and 21.15% Amharic; the remaining 0.43% spoke all other primary languages reported. The majority of the inhabitants professed Protestantism, with 54.55% of the population having reported they practiced that belief, while 24.19% of the population practiced Ethiopian Orthodox Christianity and 18.66% were Muslim.Census 2007 Tables: Oromia Region , Tables 2.1, 2.4, 2.5, 3.1, 3.2 and 3.4.
