Tax growth on commercial real estate has always been a budgetary business concern, but now the pressure has been mounting. For multifamily, it has become one of the growing operational expenses, with the top growth in a metro hitting 15.3% year over year, according to Trepp.

That's multifamily, where even with economic headwinds the basics should remain strong, as a Morningstar analysis suggested. Now try the calculation with office. Thomas Brosy at the Tax Policy Center, a venture of the Urban Institute and Brookings Institution, looked at overall falling commercial property values — in July down 12% over the previous 12 months, according to Green Street, compared to a 50% increase in residential values over 2018 — and then considered what that means to cities and the potential implications.

"The divergence in commercial and residential property values makes it hard to predict the fiscal consequences for local governments broadly," Brosy wrote. "Total property tax revenue accounts for 30 percent of local general revenue, but the pain from this transition will likely be concentrated in major cities with big commercial districts."