Over the past decade, Islip has experienced a slight decline in population, decreasing from 18,172 in 2015 to 17,284 in 2022. Despite this population decrease, the median income has shown an overall increasing trend, rising from $113,319 in 2015 to $115,930 in 2022.

The racial composition of Islip has remained relatively stable, with a predominantly white population. However, there has been a slight increase in diversity, with the Asian population growing from 2% in 2015 to 5% in 2022, and a small increase in the proportion of residents identifying as two or more races.

The lack of additional LIHTC projects in the last decade may be attributed to the city's high median income and relatively stable demographic composition. The increasing median income suggests that many residents may not qualify for low-income housing assistance, potentially reducing the demand for additional LIHTC-funded projects.

Islip's LIHTC-funded affordable housing inventory is limited to one project, Pollack Gardens, completed in 2007. This project provides 5 efficiency units, representing a small fraction of the city's estimated housing inventory. The city has received modest funding through the LIHTC program, accounting for 0.01% of New York State's total LIHTC funding. Despite a slight population decrease, Islip has experienced rising median incomes and maintained a relatively stable racial composition over the past decade. These demographic trends may have influenced the lack of additional LIHTC projects in recent years.