The office vacancy rate in major US cities hit 19.6% in Q4 2023, a new record high according to Moody's Analytics data going back to 1979. Overbuilding of offices in the 1980s-1990s during a construction boom left a supply glut, weighing on the market for decades. The 1990-1991 recession exacerbated high vacancies, and recovery was quick until the next downturn. Remote work adoption has made excess space a longer-term problem.