CREATE TABLE table_23950611_2 (market_cap_march_15__mil_usd__ VARCHAR(255), april_2013_cum_rank VARCHAR(255))
How many companies had an april 2013 cumulative ranking of 3?
    
SQL: SELECT COUNT(market_cap_march_15__mil_usd__) FROM table_23950611_2 WHERE april_2013_cum_rank = 3