Difficult Development Areas 2025

Difficult Development Areas (DDA) for the Low Income Housing Tax Credit program are designated by U.S. Department of Housing and Urban Development (HUD) and defined in statute as areas with high construction, land, and utility costs relative to its Area Median Gross Income (AMGI). DDAs in metropolitan areas are designated along Census ZIP Code Tabulation Area (ZCTA) boundaries. DDAs in non-metropolitan areas are designated along county boundaries. DDAs may not contain more than 20% of the aggregate population of metropolitan and non-metropolitan areas, which are designated separately. To learn more about Difficult Development Areas (DDA) visit: https://www.huduser.gov/portal/datasets/qct.html, for questions about the spatial attribution of this dataset, please reach out to us at [e-mail]. Data Dictionary: DD_Difficult Development Areas Date of Coverage: 2025 Last Updated: 01-2025

低收入住房税收抵免（Low Income Housing Tax Credit）项目的困难开发区（Difficult Development Areas, DDA）由美国住房与城市发展部（U.S. Department of Housing and Urban Development, HUD）划定，法定定义为相对于该区域中位总收入（Area Median Gross Income, AMGI），建筑、土地及公用事业成本偏高的区域。大都市地区的困难开发区依照人口普查邮编制表区域（Census ZIP Code Tabulation Area, ZCTA）边界划定，非大都市地区的困难开发区则依照县界划定。困难开发区的总人口不得超过单独划定的大都市与非大都市地区总人口的20%。如需了解更多困难开发区（DDA）相关信息，请访问：https://www.huduser.gov/portal/datasets/qct.html；若对本数据集的空间属性存在疑问，请致信[e-mail]与我们联系。数据字典：DD_困难开发区 覆盖日期：2025年 最后更新时间：2025年1月。