The national vacancy rate for office properties ended 2020 at 17.7%, according to recent data from Moody's Analytics REIS. That's a 90 basis point increase year-over-year and the latest dire data point for the asset class, which continues to reel from the COVID-19 pandemic and widespread WFH adoption among American companies.

Asking and effective rents were also split: asking rents lifted 0.4%, while effective rents fell 0.7%—a disparity that's "not so surprising given the typical lags we experience for a property type like the office sector during a time of economic turbulence," said Victor Calanog, head of CRE Economics at Moody's Analytics, in a recent video breaking down the firm's Office Market Update for Q4 2020.

Asking rents only began to decline in the fourth quarter, while effective rents (defined as asking rents net of concessions) began turning negative in the second quarter of 2020, Calanog said.