A1: Scheduled Arrival Time
B1: Actual Arrival Time

In C1, I would like to compute the difference between scheduled and arrival
times so I can address or look into any major delays. So far, I'm golden as
long as B1<A1 because this is a positive number. However, I get a weird
result of ###### when B1A1 because it is technically a negative number.

Any ideas on how I can write a formula to compute these negative values? Any
other suggestions for identifying late arrivals? Your help is appreciated.
Please not visual basic since I am a rookie with Excel.

Thanks