PHILADELPHIA (AP) — Federal estimates released Thursday showed that more than 16,000 residents left Philadelphia last year, marking the third straight year the city’s population has declined.

The U.S. Census Bureau data indicates Philadelphia’s population now stands at about 1.6 million residents, meaning a 1% drop occurred between July 2022 and July 2023. The data also shows that since April 2020, Philadelphia’s population declined 3.3%, or by 53,251 residents.

City officials did not respond to a request for comment, but experts noted the Census Bureau’s estimates aren’t a complete picture and don’t necessarily reflect what could happen long term.

“The question is whether or not (the population) continues to decline in the following years, or begins to slow or go back up,” Katie Martin, project director at Pew Charitable Trusts’ Philadelphia research and policy initiative, told The Philadelphia Inquirer. “We just don’t know at this point.”

The Census Bureau’s estimates take into account births, deaths and the flow of residents moving in or out of a given area in order to track changes in population.

In the last 15 years, Martin said, Philadelphia’s growth has largely been attributable to international migration of people moving to the city. That has slowed since the pandemic, while more U.S.-born residents left.