CREATE TABLE table_21550870_1 (original_air_date VARCHAR2, us_viewers__million_ VARCHAR2)

Name the original air date for 9.16 viewers
SELECT original_air_date FROM table_21550870_1 WHERE us_viewers__million_ = "9.16"
SELECT "original_air_date" FROM "table_21550870_1" WHERE "9.16" = "us_viewers__million_"