Since the Great Recession, the demand for affordable and safe rental housing has been skyrocketing, far outpacing the supply. For renters, that means the housing crisis has shown no signs of letting up.

A new report prepared by the U.S. Department of Housing and Urban Development (HUD) for Congress adds to this sobering picture of the country’s affordability crisis. It focuses on the sliver of the population with the “worst case needs”—renters who a) make at or below 50 percent of the area median income; b) do not get housing assistance; and c) pay more than half of their income on rent and/or live in physically unsafe or deficient housing.

According to HUD’s analysis, this category of renters has seen an 8 percent nationwide growth between 2013 and 2015. The number of such households now stands at 8.3 million—on its way back up to 2011’s peak of 8.5 million after a short decline. A striking 98 percent of these cases were a result of rent burdening.

Housing assistance goes a long way in helping very low-income folks navigate this new reality, but according to the report, there’s just not enough to go around. Overall, only a quarter of destitute renters received assistance. Around 43 percent had “worst case needs.” In other words, for each low income renter receiving help from the government, 1.7 went unassisted—left to bear the burden of high rents and unsafe living environments. The remaining 32 percent of the extremely low-income renters were able to navigate the private market without problems.

Of course, these nationwide averages obscure significant regional variations in need, based on local economies and housing policy. Using the information in the HUD report, CityLab created the following map. It shows the most populous 15 U.S. metros by their share of low-income renters with “worst case needs.” Miami takes the cake, with Riverside, Phoenix, and Los Angeles metros following close behind. More than half the renter populations in these four metros are in dire need of safe and affordable housing.

Not surprisingly: some of the places with the highest need—like Phoenix—also contain the smallest shares of poor renters who currently getting government help. Quite literally, renters are being left by the wayside.