Among the employees who wish to receive e-mail promotion from AdventureWorks, how many percent of them are female?
female refers to Gender = 'F'; employee who wish to receive email promotion refers to EmailPromotion = 1; percentage = DIVIDE(SUM(Gender = 'F')), (sum(Gender = 'F' or Gender = 'M'))) as percentage;
SELECT CAST(SUM(CASE WHEN T1.Gender = 'F' THEN 1 ELSE 0 END) AS REAL) * 100 / COUNT(T1.BusinessEntityID) FROM Employee AS T1 INNER JOIN Person AS T2 ON T1.BusinessEntityID = T2.BusinessEntityID WHERE T2.EmailPromotion = 1