Pay phones remaining in the US

From 2002 to 2022, e-filed tax returns climbed from about 47 million to over 150 million while US pay phones declined from roughly 2 million to near extinction, producing an inverse r of -0.9744. The most straightforward reading is that the IRS and AT&T struck a deal: for every pay phone decommissioned, one American would agree to file electronically. The pay phones, for their part, seem to have accepted this arrangement with characteristic stoicism. The booths are gone; the data remains.

Both trends are canonical indicators of digital technology displacement, running in opposite directions along the same timeline. Pay phone numbers declined as mobile phone penetration made them obsolete — from near-ubiquity in 2002 to fewer than 100,000 by 2018, with the decline accelerating as smartphone adoption crossed 50% around 2012. E-filing grew as the IRS incentivized digital submission, tax software (TurboTax, H&R Block) became consumer-grade, and the same smartphone adoption made mobile filing trivially easy. Both curves are essentially measuring 'analog to digital' at scale.

Every technology that dies and every technology that thrives during the same era will correlate, because they are both measuring the same underlying transformation. The pay phone and the e-file are bookends of the same story.