It is the average number of times that an individual, belonging to a certain area, would emigrate to outside his municipality, his territory or the C. A. of Euskadi, throughout his life in case of maintaining the same intensity to the emigration by age that observed in year t in said population group. It is calculated as the sum of emigration rates to outside your municipality by age, expressed as much as one, extended to all ages from 0 to 94 years.