A lack of affordable housing and the limited scale of housing assistance programs have contributed to the current housing crisis and to homelessness.
    The gap between the number of affordable housing units and the number of people needing them has created a housing crisis for poor people. Between 1973 and 1993, 2.2 million low-rent units disappeared from the market. These units were either abandoned, converted into condominiums or expensive apartments, or became unaffordable because of cost increases. Between 1991 and 1995, median rental costs paid by low-income renters rose 21%; at the same time, the number of low-income renters increased. Over these years, despite an improving economy, the affordable housing gap grew by one million (Daskal, 1998). By 1995, the number of low-income renters in America outstripped the number of low-cost rental units by 4.4 million rental units - the largest shortfall on record (Daskal, 1998). More recently, the strong economy has caused rents to soar, putting housing out of reach for the poorest Americans. Between 1995 and 1997, rents increased faster than income for the 20% of American households with the lowest incomes (U.S. Department of Housing and Urban Development, 1999). This same study found that the number of housing units that rent for less than $300, adjusted for inflation, declined from 6.8 million in 1996 to 5.5 million in 1998, a 19 percent drop of 1.3 million units. The loss of affordable housing puts even greater numbers of people at risk of homelessness.
    The lack of affordable housing has lead to high rent burdens (rents which absorb a high proportion of income), overcrowding, and substandard housing. These phenomena, in turn, have not only forced many people to become homeless; they have put a large and growing number of people at risk of becoming homeless. A recent Housing and Urban Development (HUD) study found that 5.3 million unassisted, very low-income households had "worst case needs" for housing assistance in 1995 (U.S. Department of Housing and Urban Development, 1998).3 This figure is an all-time high and represents an 8% increase over the 1989 figure.
    Housing assistance can make the difference between stable housing, precarious housing, or no housing at all. However, the demand for assisted housing clearly exceeds the supply: only about one-third of poor renter households receive a housing subsidy from the federal, state, or a local government (Daskal, 1998). The limited level of housing assistance means that most poor families and individuals seeking housing assistance are placed on long waiting lists. From 1996-1998, the time households spent on waiting lists for HUD housing assistance grew dramatically. For the largest public housing authorities, a family's average time on a waiting list rose from 22 to 33 months from 1996 to 1998 - a 50% increase (U.S. Department of Housing and Urban Development, 1999). The average waiting period for a Section 8 rental assistance voucher rose from 26 months to 28 months between 1996 and 1998.4 Excessive waiting lists for public housing mean that people must remain in shelters or inadequate housing arrangements longer. Consequently, there is less shelter space available for other homeless people, who must find shelter elsewhere or live on the streets.
    A housing trend with a particularly severe impact on homelessness is the loss of single room occupancy (SRO) housing. In the past, SRO housing served to house many poor individuals, including poor persons suffering from mental illness or substance abuse. From 1970 to the mid-1980s, an estimated one million SRO units were demolished (Dolbeare, 1996). The demolition of SRO housing was most notable in large cities: between 1970-1982, New York City lost 87% of its $200 per month or less SRO stock; Chicago experienced the total elimination of cubicle hotels; and by 1985, Los Angeles had lost more than half of its downtown SRO housing (Koegel, et al, 1996). From 1975 to 1988, San Francisco lost 43% of its stock of low-cost residential hotels; from 1970 to 1986, Portland, Oregon lost 59% of its residential hotels; and from 1971 to 1981, Denver lost 64% of its SRO hotels (Wright and Rubin, 1997). Thus the destruction of SRO housing is a major factor in the growth of homelessness in many cities.
    Finally, it should be noted that the largest federal housing assistance program is the entitlement to deduct mortgage interest from income for tax purposes. In fact, for every one dollar spent on low income housing programs, the federal treasury loses four dollars to housing-related tax expenditures, 75% of which benefit households in the top fifth of income distribution (Dolbeare, 1996). Moreover, in 1994 the top fifth of households received 61% of all federal housing benefits (tax and direct), while the bottom fifth received only 18%. Thus, federal housing policy has thus not responded to the needs of low-income households, while disproportionately benefitting the wealthiest Americans.