 The driest month of the year is September with an average of of precipitation over 7.3 days.In Orsières about 917 or (34.9%) of the population have completed non-mandatory upper secondary education, and 198 or (7.5%) have completed additional higher education (either university or a "Fachhochschule").Of the 198 who completed tertiary schooling, 63.6% were Swiss men, 23.2% were Swiss women, 7.6% were non-Swiss men and 5.6% were non-Swiss women.