Why is this important?
The level of population growth is a fundamental benchmark of how attractive Long Island is as a place to live.  New residents require more housing and services, but can also add to the vibrancy of growing communities, increase sales for local businesses and provide additional tax revenues.  Growth in the working age population is also essential to Long Island’s economy.  Over the long run, slow growth in the number of workers makes it difficult for businesses to expand or even remain in business.  Increasing diversity can provide a cultural richness that many people value, but can also add to social tensions.  In addition, some economists have found that workforce diversity leads to a stronger regional economy.

How are we doing?
Long Island has continued to see modest growth in its population according to annual surveys conducted by the U.S. Census and the newest 2010 Census, the first full count of the population since 2000. This indicates that Long Island’s quality of life continues to attract residents in spite high housing and other costs. Continuing a long-term trend, Suffolk, at a growth rate of 5%, has attracted most of the new population while Nassau experienced almost no growth (0.4% growth rate).

Age distribution
Along with the rest of the nation, Long Island’s population continues to age, a result of the large “baby boom” cohort entering their retirement years, low birth rates in the 1970s and early 1980s, and longer life expectancies.  This can be seen in changes in different age groups.  The number of people over 45 grew rapidly between 2000 and 2010, while those in their 30s and early 40s declined.  Those between the ages of 15 and 24 increased after two decades of decline.  Migration, both foreign immigration and migration to and from other parts of the United States also affect the shape of Long Island’s age distribution.  A comparison of Long Island to the U.S. and other parts of the region for two age groups, those in their late 20s and early 30s and those over 55, indicates that economic, cost of living and other factors are accentuating these trends on Long Island.

Long Island has the lowest share of young adults (25-34 years of age) in the region and has seen this age group decline faster than other parts of the region. In 2010, it had 12% fewer people aged 25 to 34 in 2010 than in 2000, resulting in a share of 11% of the 2010 population.  Nationally, this cohort increased by 4% and represents 13.3% of the U.S. population. In New York City, this age group grew by 3%.  Although the number of young adults declined throughout the New York suburbs,, they declined more rapidly on Long Island than in northern New Jersey, southwestern Connecticut and the Hudson Valley. As for older adults, the share of the Long Island population that is over 55 has increased by 21%, slightly faster than the rest of the region (20%) but slower than the nation as a whole (30%).

Race and Ethnicity
Long Island continued its long-term trend toward greater racial to diversity in the last decade.  Nearly a third of Long Islanders (31%) are now of Hispanic, Black, Asian or other non-White origin.  This is a substantial increase from 24% non-white in 2000.  Still,69% of Long Island residents who are white represent a higher share than in the other suburbs in the region  or for the U.S. (64%).  Most of the growth came from Hispanic and Asian residents, both of whom increased by 56% over the decade.  Black residents increased by 9% while White residents decreased by 8%.

Migration
The trend of people leaving Long Island for other parts of the U.S. had largely slowed down since the peak in 2005 and 2006. As in other parts of the U.S., a weak housing market made it difficult for many to sell their homes and move elsewhere.  The stagnant national job market also slowed career mobility.  In 2009 Long Island had an out-migration of 55,813, the lowest since 2000. Meanwhile, the number of people moving to Long Island was stable for three years after a slight drop in 2006. A decreasing out-migration and a stagnant in-migration resulted in a nearly zero net migration in 2009. All the statistics do not include foreign migrations because of lack in reliable annual data.

Most of the people coming to Long Island are still from New York City but the number had been going down. In 2009 28,878 people moved from New York City to Long Island, 18% fewer than the number in 2007. Outside the tri-state region, new Long Island residents were most likely from Florida, California and Pennsylvania.

For the people who left Long Island in 2009, nearly half of them went to the rest of the tri-state region. The popular destinations outside the region continued to be Florida, North Carolina, Pennsylvania, California, and Texas, the sunnier or lower-tax states.

As for the movement between the two counties on Long Island, the trend of people moving further out from Nassau County to Suffolk County had steadily slowed down between 2006 and 2009. In 2009 the Nassau-to-Suffolk movement dropped by over a third compared to the 2006 number.