There are a lot of variables to consider, as mentioned above, so it's up to you to weigh in your mind how hard did the guide work for you. On my moose hunt in AK last fall, our guide not once spotted any, NOT ONE, game animal before my buddy and I did. We could out walk him too, up hill or down!! BUT after I put my moose down, we helped cape and de-bone and then HE carried more than his share of weight when we packed the meat back to camp, plus he fixed all of our meals and carried survival gear every where we went, cleaned the pots and pans, and we had good conversation for 10 days! He also carried all of the caribou meat to the pick up point, as fast as we could butcher, he was back for another load and he was carrying the caribou meat about a quarter mile!So we took it all into account, weighed the pluses and minuses, and tipped what we thought was appropriate, and he seemed quite pleased!! When we were leaving, we invited him to the lower states to hunt on our private property and he invited us up for some fishing!!
I actually asked him what the best tip was that he had ever recieved and it was a new .500 S&W from a S&W rep. that had hunted with him.