A number of researchers (David Rodda, Jacob Vigdor, and Janna Matlack), argue that a shortage of affordable housing – at least in the US – is caused in part by income inequality. David Rodda noted that from 1984 and 1991, the number of quality rental units decreased as the demand for higher quality housing increased (Rhoda 1994:148). Through gentrification of older neighbourhoods, for example, in East New York, rental prices increased rapidly as landlords found new residents willing to pay higher market rate for housing and left lower income families without rental units. The ad valorem property tax policy combined with rising prices made it difficult or impossible for low income residents to keep pace.
What do a number of researchers think a shortage of is caused in part by income inequality? What decreased in number between 1984 and 1991? Why did the demand for rentals decrease? What drove increased rental prices in East New York? What combined with ricing prices to make it difficult or impossible for poor people to keep pace?