Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_203_153 ( id number, "stamp issue date" text, "stamp set" text, "#cards" text, "card set ref" text, "qty. issued" number )

### Question ###
which year had the most stamps issued ?

### Accurate SQL ###

SELECT "stamp issue date" FROM table_203_153 GROUP BY "stamp issue date" ORDER BY SUM("qty. issued") DESC LIMIT 1