The answer to the question is ZERO, but when you have 3 combines you are 3 times more likely to have a breakown, are you not. If one of the three combines breaksdown, the entire operation can be affected. Combine n2 comes over to help, combine n3 has to wait while the cart operator is helping unplug combine n1, and so on. We also find we hit the field early because only one machine to service. It can also run straight through meals and later into the evening.