Calculate the percentage of sales done at Sac State American River Courtyard.
percentage =   MULTIPLY(DIVIDE(SUM(LocationName = 'Sac State American River Courtyard'), COUNT(LocationID)), 1.0); Sac State American River Courtyard refers to LocationName = 'Sac State American River Courtyard';
SELECT CAST(COUNT(CASE WHEN T2.LocationName = 'Sac State American River Courtyard' THEN 1 ELSE NULL END) AS REAL) * 100 / COUNT(T1.TransactionID) FROM `transaction` AS T1 INNER JOIN location AS T2 ON T1.LocationID = T2.LocationID