A Difficult Development Area (DDA) for the Low Income Housing Tax Credit program is an area designated by U.S. Department of Housing and Urban Development (HUD) with high construction, land, and utility costs relative to its Area Median Gross Income (AMGI). All designated DDAs in Metropolitan Statistical Areas (MSA) or Primary Metropolitan Statistical Areas (PMSA) may not contain more than 20% of the aggregate population of all MSAs/PMSAs, and all designated areas not in metropolitan areas may not contain more than 20% of the aggregate population of the non-metropolitan counties. Data is current as of: 09/11/2013This layer is intended for researchers, students, policy makers, and the general public for reference and mapping purposes, and may be used for basic applications such as viewing, querying, and map output production. This layer will provide a basemap for layers related to socio-political analysis, statistical enumeration and analysis, or to support graphical overlays and analysis with other spatial data. More advanced user applications may focus on demographics, urban and rural land use planning, socio-economic analysis and related areas (including defining boundaries, managing assets and facilities, integrating attribute databases with geographic features, spatial analysis, and presentation output.)