What is the percentage of wholesaler customers who have shipment weight of not greater than 70000 pounds?
"wholesaler" is the cust_type; weight of not greater than 70000 pounds refers to weight < 70000; percentage = Divide (Count(cust_id where weight < 70000), Count(cust_id)) * 100
SELECT CAST(SUM(CASE WHEN T2.weight < 70000 THEN 1 ELSE 0 END) AS REAL) * 100 / COUNT(*) FROM customer AS T1 INNER JOIN shipment AS T2 ON T1.cust_id = T2.cust_id WHERE T1.cust_type = 'wholesaler'