CREATE TABLE table_54280 ("IWCR No." TEXT, "Name" TEXT, "Wheel arrangement" TEXT, "SR No." TEXT, "Year made" FLOAT, "Year withdrawn" FLOAT)

What is the mean Year when the IWCR number was 5 and the Year withdrawn was bigger than 1926?
SELECT AVG("Year made") FROM table_54280 WHERE "IWCR No." = '5' AND "Year withdrawn" > '1926'
SELECT AVG("Year made") FROM "table_54280" WHERE "IWCR No." = '5' AND "Year withdrawn" > '1926'