Calculate the percentage of female students.
percentage = CONCAT(DIVIDE(MULTIPLY(COUNT(person.name which is not in male.name)), 100), COUNT(person.name that is IN male.name),'%'); female students refers to person.name who are NOT in male.name;
SELECT CAST(SUM(IIF(T2.name IS NULL, 1, 0)) AS REAL) * 100 / COUNT(T1.name) FROM person AS T1 LEFT JOIN male AS T2 ON T2.name = T1.name
database name:db_id student_loan
bool table bool Cols: name dtype text, 
person table person Cols: name dtype text, 
disabled table disabled Cols: name dtype text, 
enlist table enlist Cols: name dtype text, organization dtype text, 
filed_for_bankruptcy table filed_for_bankruptcy Cols: name dtype text, 
longest_absense_from_school table longest_absense_from_school Cols: name dtype text, month dtype integer, 
male table male Cols: name dtype text, 
no_payment_due table no_payment_due Cols: name dtype text, bool dtype text, 
unemployed table unemployed Cols: name dtype text, 
enrolled table enrolled Cols: name dtype text, school dtype text, month dtype integer, 
