what is the official rating 16-39 for the episode with  a 16-39 share of 22,77%?
create table table_29804176_23 (official_rating_16_39 varchar, share_16_39 varchar, PRIMARY KEY (official_rating_16_39))
select official_rating_16_39 from table_29804176_23 where share_16_39 = "22,77%"