CREATE TABLE table_name_66 (number_of_clubs INTEGER, fourth_placed VARCHAR(255), season VARCHAR(255))
What is the number of clubs before 2003 with a 4th place winner of Shenzhen Jianlibao?
    
SQL: SELECT AVG(number_of_clubs) FROM table_name_66 WHERE fourth_placed = "shenzhen jianlibao" AND season < 2003