I want to calculate whether the perigee / apogee of the Moon always takes place at the exact same distances (radius to Earth) as measured by the LLR (Lunar Laser Ranging). I trust that we know the size of the orbit of the moon very exactly, and also that the orbit is growing larger. But I want to check whether calculation of the perigee / apogee happens the exact same distance as measured, to test if there should be any (periodical) distance (radius) anomaly. My questions are; Is that already done? Does it already exsist such software? Who is into that “business” ?