FH is right about full scale, but I trim my planes to fly straight and level at a particualr throttle setting (a comfortable cruise), and then fly. I have become accustomed to holding a bit of down, or up, or whatever to keep the plane flying as I want it to. I almost never retrim the plane for throttle changes, and NEVER for wind conditions. (If the plane is trimmed to fly straight and level, then trim changes for wind don't make sense; you'd have to trim for downwind flight, then retrim for upwind, or crosswind.
Dennis-