Approximate focal length of a Stäckel approximation to MWPotential2014 computed using the relation in Equation (9) in Sanders (2012). The focal length is shown on a grid in angular momentum and random energy over a large range of relevant orbits. The guiding-star radii for the range of angular momenta shown range from 0.2 kpc to 117 kpc; the energy for each angular momentum ranges from that of the circular orbit with that angular momentum to the escape energy. This figure can be used to establish an approximate focal length for using the Stäckel approximation for MWPotential2014.