Catham has just passed a city ordinance that limits the student-teacher ratio in its public school system to 25:1. All Chatham children residing in the city have access to the Chatham public school system for free. Parents have the option of sending their children to a private high school where tuition is $10,000 per year. When a recession occurs and average incomes fall, the number of children enrolled in the Chatham public school system tends to increase. Therefore, though most employment opportunities contract in economic recessions, getting a teaching job in Chatham's public school system will not be made more difficult by a recession.
Which of the following would be most important to determine in order to evaluate the argument?