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The last census in Mexico that asked for an individual's race, which was taken in 1921, indicated that 50.09% of the population identified as Mestizo (mixed Amerindian and European descent). The second-largest group was whites at 36.33% of the population. The third-largest group was the "pure indigenous" population, constituting 12.76% of the population. The remaining 0.82% of the population of Chihuahua was considered "other", i.e., neither Mestizo, indigenous, nor white. The most important indigenous tribes of the state of Chihuahua are:

The last census in Mexico that asked for race was carried out in which year?
1921