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_2639433_4 (market_share__target_group_14_49_ VARCHAR, viewers__in_millions_target_group_14_49_ VARCHAR)

### Question ###
How many times was the viewer target group 0.63?

### Accurate SQL ###

SELECT COUNT(market_share__target_group_14_49_) FROM table_2639433_4 WHERE viewers__in_millions_target_group_14_49_ = "0.63"