> Subway ridership is up 75% since 1980. The capital budget during the 1980s averaged $3.4 billion annually in 2020 dollars: https://wagner.nyu.edu/files/faculty/publications/rescue.pdf (fig. 5). The 2015-2019 capital program (5 years) averaged about $6.5 billion 2020 dollars. So a 90% increase in capital spending for a 75% increase in ridership. Punchline: MTA is so massively wasteful, that wasn't enough. The system deteriorated the whole time leading to catastrophic failure in the last few years.

Just because the spend per rider increased over that time doesn't mean the system is getting what it needs though. A newer system will usually function better than a starved system years later naturally because of deferred maintenance and other aging infrastructure ailments even if the per rider numbers have increased. Comparing it just on the per rider spend assumes that the earlier number is enough.