Greenhorn has a point, for example,
A 200 fps arrow at 40 yards is 50 fps/yard but
at 300 fps you could shoot 60 yards and still get 50 fps/yard performance.
If the wind was at your back, say 10 mph, that would add another 1/6 mile per minute, or 1/360 mile per second, or 5280/360 feet per second or 528/36 or 264/18 or 132/9 or 44/3 or 11.3 fps and you could shoot over 60 yards then. The arrow would get there with the same fps/yard performance as the 40 yard shot.
It helps to have a chart with this stuff taped on your bow, right Greenhorn?
If we were shooting down, we'd get another 32 ft per sec per sec, but it would depend on the sin or cos of the angle down somehow. What do you do for that condition Greenhorn?
I know you don't like those big spotting scopes, they take into account the curvature of the earth and that helps too, so how do you do it?