As noted above by the other writers it is strongly dependent on aircraft type. Don't read the above and apply the results to a standard fully symmetrical airplane (I know it was not in question). A lot of guys assume that since those kinds of airplanes being discussed require a down tail load that it is needed for all airplanes.

If there is no fuselage pitching moment and the airplane uses a symmetrical airfoil the tail is actually lifting at all angles of attack. It is only when you have moments due to airfoil, flaps, fuselages, gear, etc. that the load shifts downward. Of course 98 percent of the things flying fit in the later catagory!