Hard data has been hard to come by regarding people leaving cities during COVID-19. Did 500,000 flee Manhattan? Did San Francisco empty out? Here is data from the CBRE report:

In this comparison of 2020 and 2019 migration data, several big cities fared the worst: San Francisco, New York, Seattle, Los Angeles, and Washington, D.C. Sacramento did well because of spillover effects from the Bay Area.

In terms of actual numbers for cities, here is a summary of the same data for New York City:

By analysing US Postal Service address changes over the last 12 months, the study reveals the greatest out-migration of people is, as expected, from Manhattan, with nine of the 10 zip codes with the largest outflows of residents in the city located in the borough…

In terms of hard numbers, the four zip codes in Manhattan from the Hudson to the East River between 42nd Street and 59th Street lost more than 12,000 residents in 2020. In 2019 that figure was less than 3,000…

The streets may have felt even emptier than the data implies, as the study only looked at permanent address changes – the total number of those who left the city for significant portions of the pandemic is likely much higher. Many more people temporarily left to stay with family or at seasonal rentals…

Talk of an exodus from New York may be a little exaggerated as 41 per cent of Manhattan residents who moved in 2020 stayed in the borough, presumably taking advantage of cheaper rents to upgrade their living space. Prior to Covid, this figure was just below 50 per cent.

The last part quoted above is important: the number of permanent address changes was smaller than it may have appeared. Plenty of people left Manhattan and other urban locations but they did not necessarily give up on their property and may return when COVID-19 fades away. Similarly, the impact on suburbs that took in new residents during COVID-19 may then also see population shifts after COVID-19 as people return to urban neighborhoods.