Step 2. To begin equalizing district populations, add or subtract political subdivisions of the next smaller size in a compact manner beginning at the common border of the largest political subdivisions.
Avoid splitting more than one subdivision between any pair of adjacent districts. This preempts the selection of territory based upon partisan goals of packing or cracking. Try to choose subdivisions that optimize compactness for both the supplying district and the receiving district.
After subdividing Allegheny and Philadelphia Counties to create approximately population districts, the analysis steps to the township/borough level. Population adjustments take place to narrow the district population variances toward the target. The two examples show one option to adjust the populations of Districts 16 and 1.
A The eight counties of District 16 host a total population of 841,313 persons, more than allowed. Shifting several townships and boroughs in the southwest corner of Butler County with a combined population of 77,421 persons to District 15 brings the District 16 population to 763,892 persons, much closer to the 764,865 person target, but now slightly under-populated.
B Similarly, District 1 after Step 1 includes Bucks County, population 646,538 persons. Adding seven municipalities in Montgomery County that abut Bucks, plus an enclosed Hatfield Borough and adjoining Lansdale Borough, brings the district population to 766,087 persons, only slightly too high.