Keep your bike inside the office, or at least a parking garage, if you can. It'll save you the worry of having to think about whether it'll still be there when you clock out for the day. Of course, when you get home, you should absolutely keep your ride indoors (unless you have the convenience of having a garage). If you're using your bike heavily, or have a particularly nice ride, there's really no good reason to be storing it outside.
Take Your Bike Indoors If Possible