Among the shipments to a customer from Texas, what percentage of the shipments shipped in 2017?
"Texas" refers to state = 'TX'; shipped in 2017 refers to CAST(ship_date AS DATE) = 2017; percentage = Divide (Count (ship_id where CAST(ship_date AS DATE) = 2017), Count (ship_id)) * 100
SELECT CAST(SUM(CASE WHEN STRFTIME('%Y', T1.ship_date) = '2017' THEN 1 ELSE 0 END) AS REAL ) * 100 / COUNT(*) FROM shipment AS T1 INNER JOIN customer AS T2 ON T1.cust_id = T2.cust_id WHERE T2.state = 'TX'