Compare the graduate cohort for Auburn University from 2011 to 2013?
graduate cohort for Auburn University refers to grad_cohort is not null WHERE chronname = 'Auburn University', gender = 'B', race = 'X' and cohort = '4y other', '4y bach'; from 2011 to 2013 refers to year in (2011, 2012, 2013);
SELECT SUM(CASE WHEN T2.year = 2011 THEN T2.grad_cohort ELSE 0 END), SUM(CASE WHEN T2.year = 2012 THEN T2.grad_cohort ELSE 0 END), SUM(CASE WHEN T2.year = 2013 THEN T2.grad_cohort ELSE 0 END) FROM institution_details AS T1 INNER JOIN institution_grads AS T2 ON T1.unitid = T2.unitid WHERE T2.gender = 'B' AND T2.race = 'X' AND T1.chronname = 'Auburn University'