SELECT COUNT("Runner-up") FROM table_37594 WHERE "Last win" < '1998' AND "Wins" = '1' AND "Rank" > '13'
Which Runner-up has a Last win smaller than 1998, and Wins of 1, and a Rank larger than 13?
CREATE TABLE table_37594 (
    "Rank" real,
    "Club" text,
    "Wins" real,
    "Last win" real,
    "Runner-up" real,
    "Last losing final" text
)