surement error in the ancient time was much greater, so no accuracy would be lost by adjusting the anomalistic month to this value. The problem is that this particular <span class="nowrap">P<sub>a</sub></span> is not a simple fraction and is inconvenient for almanac calculations. So the almanac makers would prefer to choose another value that could both be close to the observation value within measurement error and could be expressed as a simpler fraction. The larger N is, the easier it is to find a simpler