Counting multiple Conditions

Hey Forum,

I am new on here and hope someone can be so kind as to help me with a formula problem that is bugging me..

So I am looking at 4 different totals -

Eg.

5 Managers
5 Supervisors
5 Team Leaders
5 Shift Workers

It is based on a calender and at any one time i need one crew available (1 Manager, 1 Supervisor, 1 Team Ldr and 1 Shift Worker to make one complete crew)

Is there a formula that can count how many available crews i will have according to how many of each type of staff are available?

Some days I may only have 1 supervisor but 5 managers, 5 supervisors and 5 Shift workers although this would result in 1 crew available...

Really hope someone can help..