Pay phones remaining in the US

As pay phones have disappeared and air quality has improved, both with near-perfect inverse precision (-0.988), one is tempted to conclude that pay phones were somehow polluting the atmosphere. They were not, but the chart makes a compelling visual case that removing phone booths from street corners has improved the American lung. Superman has no place to change, but he can breathe easier.

Pay phones declined from about 1.7 million to under 100,000 as smartphones made them obsolete. Air quality improved as emissions regulations took effect. Both are smooth monotonic trends across twenty-one years, moving in opposite directions. The smartphone that killed the pay phone is also the device that, through various indirect channels, has enabled more efficient logistics, remote work, and reduced commuting—all of which may have marginally improved air quality. But the primary drivers are different: technology obsolescence for the phones, environmental regulation for the air.

Twenty-one years of fewer pay phones and cleaner air is a correlation that captures the dual modernization of American infrastructure: the physical (removing obsolete technology) and the environmental (cleaning the atmosphere). Both happened simultaneously, both were driven by different policies, and both are measures of a country that has gotten better at some things while the scatter plot remained clueless about why. The booth is empty. The air is clear. The correlation is transparent.