Among all the male officers, what is the percentage of them are White?
male refers to gender = 'M'; white refers to race = 'W'; percentage = divide(count(officers where race = 'W'), count(officers)) where gender = 'M' * 100%
SELECT CAST(SUM(IIF(race = 'W', 1, 0)) AS REAL) * 100 / COUNT(case_number) FROM officers WHERE gender = 'M'