then why did the city's vacancy rate drop to a mere 1.4 percent

Not to worry Commomone, the empty apartments should be filled soon.

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“There are enough vacant apartments in New York City’s public and supportive housing systems to accommodate 15,000 people, according to data shared with the New York Daily News by Brooklyn Councilman Lincoln Restler, who’s questioning why Mayor Eric Adams’ administration isn’t doing more to fill those units amid the continuing migrant crisis.”

governing.com - NYC beds lay empty as mayor opens costly migrant shelters

Scrolling down on your link real New Yorkers are struggling.

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“New Yorkers are Struggling to Pay Their Rent

New York City is becoming more expensive, and homes are increasingly out of reach for low- and moderate-income New Yorkers. As the economic landscape evolves following the pandemic, residents are grappling with heightened financial strains, feeling the impact of economic pressures more acutely than ever. With housing costs skyrocketing and a surge in living expenses, not to mention inflation, many New Yorkers are experiencing increased difficulty making ends meet.

The city's residents are facing unprecedented financial challenges, reflected in high rent burdens, missed payments, and an alarming increase in the number of households struggling with economic insecurities.“