National Insights

Let's talk about stats (Part 1 of 2)

Population density in New York City
By Constantine A. Valhouli  |  August 5, 2017 2:35 PM

Image by Vincent Desjardins via Creative Commons

The metrics we choose affect what will be measured. And the parameters we choose to work within can have an equally profound effect on the outcome of a study.

Let's consider the population density of New York City.

New York City is, by far, the largest city in the United States with a population of just over 8,175,000 people. For context, the second largest city, Los Angeles, has less than half of New York City's population.

According to the U.S. Census, the population density for New York City overall is just over 27,000 people per square mile. This assumes 8.175 million people living in 302.6 square miles.

But when we think of New York City, it is often only Manhattan that comes to mind. Manhattan is 22 square miles (just 7.1% of the city's land) and has 1.6 million residents (roughly 20% of city's total population). This works out to an average population density of almost 73,000 people per square mile.

But that average doesn't tell the whole story. The population isn't spread evenly across Manhattan. A low-rise historic district like the West Village (approximately 24,000 people in 272 acres, or 0.425 square miles) has a population density of 56,000 people per square mile – only 76% of the average density of Manhattan. But even within the West Village, the density varies from 38,000 (just 52% of the average density of Manhattan) to 88,000, depending on the census tract.

But, as always, metrics matter. Some studies use not the city itself, but the broader "urban area" as a point of comparison. According to Wendell Cox of Demographia, "The New York urban area covers the most land area in the world. It stretches ... 50 miles west to Hackettstown, New Jersey; 90 miles east to Sag Harbor Long Island; 55 miles north to Duchess County, New York; and 80 miles south to Ocean County, New Jersey. The New York urban area is geographically bigger than Delaware and Rhode Island combined." For reference, Delaware and Rhode Island are 2,491 and 1,212 square miles, respectively.

Let's review those numbers again.

Manhattan's 22 square miles have 1.6 million people. New York City's 302 square miles have 8.17 million people. And the NYC ''urban area" - which covers more than 3,700 square miles, has 18 million people. In other words, the population in the city's 300 square miles isn't doubled until we add the population of the surrounding 3,400 square miles. The population density for the New York City 'urban area' is just 4,865 per square mile.

Metrics – and parameters – matter.

And Let's talk about stats (Part 2) – measuring LGBTQ population, and why this can affect policy – is live, too.

Constantine A. Valhouli is the Director of Research for NeighborhoodX.