CREATE TABLE table_203_153 (id NUMBER, "stamp issue date" CLOB, "stamp set" CLOB, "#cards" CLOB, "card set ref" CLOB, "qty. issued" NUMBER)

which year had the most stamps issued ?
SELECT "stamp issue date" FROM table_203_153 GROUP BY "stamp issue date" ORDER BY SUM("qty. issued") DESC LIMIT 1
SELECT "stamp issue date" FROM "table_203_153" GROUP BY "stamp issue date" ORDER BY SUM("qty. issued") DESC FETCH FIRST 1 ROWS ONLY