Question: What was the free dance score in the event where compulsory dance score was 15.99?
Schema: create table table_22644589_4 (free_dance__fd_ varchar, compulsory_dance__cd_ varchar, PRIMARY KEY (free_dance__fd_))
SQL: select free_dance__fd_ from table_22644589_4 where compulsory_dance__cd_ = "15.99"