Housing discrimination helps reinforce residential segregation through mortgage discrimination, redlining, and predatory lending practices. Another barrier is discriminatory mortgage lending patterns and redlining. Retail redlining is a spatially discriminatory practice among retailers. Absentee landlordism and mortgage redlining also characterize disinvestment. The East-West racial divide is a legacy of redlining and blockbusting in Cleveland. Practices included redlining, zoning, and colorblind adaptation planning. The allegations of "redlining" certain neighborhoods originated with the Federal Housing Administration in the 1930s. Prior to neighborhood desegregation and redlining, Oak Cliff was predominantly white. The result of the establishment of the FHA was redlining. HOLC is often cited as the originator of mortgage redlining. Two decisions in the 1960s exacerbated the trends begun with redlining. Document level security, DWG redlining, and the document creation wizard were also added. This practice, known as redlining, was made illegal by the Fair Housing Act of 1968. Real estate agents and white homeowners often used a tactic called redlining. The commission also documented blanket refusals to lend in particular areas (redlining).