+3, 4 or whatever number we're up to now from what Ard said
I try amd make it a point to go to a local shop and pick up a few flys that are fishing well locally. More often than not, I'll walk out with the flys, whatever else I pick up and new information. If I plan on going back to that area, I'll generally save one of the most effective patterns and use it as a sample so that I can tie some up when I go back to fish that area. This is not to say that I won't go back to the shop to pick up more the next time I return. Seems there's always something that's working that I don't have in my box!