Non-white people are also overrepresented in homeless populations, with such groups two and one-half times more likely to be homeless in the U.S. The median age of homeless people is approximately 35. Statistics for developed countries
In 2005, an estimated 100 million people worldwide were homeless. The following statistics indicate the approximate average number of homeless people at any one time. Each country has a different approach to counting homeless people, and estimates of homelessness made by different organizations vary wildly, so comparisons should be made with caution. European Union: 3,000,000 (UN-HABITAT 2004)
England: 11,580 single households were assessed as rough sleeping at the point of approach in 2021, up 39% from 2019–20, with 119,400 households owed a prevention duty in 2020–21 
Scotland: 27,571 households were assessed as homeless in 2020/21, a decrease of 13% compared to 2019/20 
Canada: 150,000
Australia: On census night in 2006 there were 105,000 people homeless across Australia, an increase from the 99,900 Australians who were counted as homeless in the 2001 census 
United States: The HUD 2018 Annual Homeless Assessment Report (AHAR) to Congress reports that in a single night, roughly 553,000 people were experiencing homelessness in the United States. According to HUDs July 2010 fifth Homeless Assessment Report to Congress, in a single night in January 2010, single-point analysis reported to HUD showed 649,917 people experiencing homelessness. This number had increased from January 2009s 643,067. The unsheltered count increased by 2.8 percent while the sheltered count remained the same.
Schneider described schizoaffective disorders as "cases in-between" the traditional Kraepelinian dichotomy of schizophrenia and mood disorders.The historical clinical observation that schizoaffective disorder is an overlap of schizophrenia and mood disorders is explained by genes for both illnesses being present in individuals with schizoaffective disorder; specifically, recent research shows that schizophrenia and mood disorders share common genes and polygenic variations. Schizoaffective disorder was included as a subtype of schizophrenia in DSM-I and DSM-II, though research showed a schizophrenic cluster of symptoms in individuals with a family history of mood disorders whose illness course, other symptoms and treatment outcome were otherwise more akin to bipolar disorder than to schizophrenia. DSM-III placed schizoaffective disorder in "Psychotic Disorders Not Otherwise Specified" before being formally recognized in DSM-III-R. DSM-III-R included its own diagnostic criteria as well as the subtypes, bipolar and depressive. In DSM-IV, published in 1994, schizoaffective disorders belonged to the category "Other Psychotic Disorders" and included almost the same criteria and the same subtypes of illness as DSM-III-R, with the addition of mixed bipolar symptomatology.DSM-IV and DSM-IV-TR (published in 2000) criteria for schizoaffective disorder were poorly defined and poorly operationalized. These ambiguous and unreliable criteria lasted 19 years and led clinicians to significantly overuse the schizoaffective disorder diagnosis. Patients commonly diagnosed with DSM-IV schizoaffective disorder showed a clinical picture at time of diagnosis that appeared different from schizophrenia or psychotic mood disorders using DSM-IV criteria, but who as a group, were longitudinally determined to have outcomes indistinguishable from those with mood disorders with or without psychotic features.