I used to be able to enter a date in the format MM/DD and it would be recognized as a date, and as such formatted to whatever the date format set for that cell had been set to (for example, YYYY-MM-DD). (eg) I would enter 10/1, hit enter, and the cell (having a DATE format) would change it to 2013-10-1
Now, however, it just leaves it as text instead of converting it to a date. Very frustrating. How can I change this behaviour to what it used to be / what I want?