A return-to-normal gauge to watch is mass transit ridership, which continues to creep higher in parts of the country as people get vaccinated and emerge from lockdown.
Why it matters: Ridership return is key for the big city systems — think San Francisco or New York — that are more reliant on fares for revenue.
Other transit systems rely primarily on a variety of funding sources, like sales tax (which also took a pandemic hit).
Flashback: City and state financials aren't as dire as expected initially when the pandemic first hit, thanks to government stimulus and the nature of the recovery, says Cooper Howard, a municipal strategist at Charles Schwab.
"The better the fiscal situation for the state or city, the more flexibility they have to provide support to that transit agency," Howard says.
Worth noting: Car trips in New York City are much closer to pre-pandemic levels, according to MTA bridge and tunnel figures.
Bus ridership in NYC has also recovered faster than the subway.
What to watch: If riders don't return — or do so with less frequency — thanks to holdover pandemic habits. (Though some essential workers have relied on public transit all along.)
More work from home or permanent relocation to suburban areas could cause a small but permanent drop in transit ridership, per a recent Moody's report on systems in New York, France, London and British Columbia.
But forever drop-offs in those areas could be mitigated by "new transit users from population and business growth as well as new infrastructure capacity."