When was an average speed of 81.388 mph recorded?
CREATE TABLE table_2266976_1 (date VARCHAR, average_speed__mph_ VARCHAR)
SELECT date FROM table_2266976_1 WHERE average_speed__mph_ = "81.388"
### Context: CREATE TABLE table_2266976_1 (date VARCHAR, average_speed__mph_ VARCHAR) ### Question: When was an average speed of 81.388 mph recorded? ### Answer: SELECT date FROM table_2266976_1 WHERE average_speed__mph_ = "81.388"