USA Census 2020 Redistricting Tracts

This layer contains census tract level 2020 Decennial Census redistricting data as reported by the U.S. Census Bureau for all states plus DC and Puerto Rico. The attributes come from the 2020 Public Law 94-171 (P.L. 94-171) tables. Data download date: August 12, 2021 Census tables: P1, P2, P3, P4, H1, P5, Header Downloaded from: Census FTP site Processing Notes: Data was downloaded from the U.S. Census Bureau FTP site, imported into SAS format and joined to the 2020 TIGER boundaries. Boundaries are sourced from the 2020 TIGER/Line Geodatabases. Boundaries have been projected into Web Mercator and each attribute has been given a clear descriptive alias name. No alterations have been made to the vertices of the data. Each attribute maintains it's specified name from Census, but also has a descriptive alias name and long description derived from the technical documentation provided by the Census. For a detailed list of the attributes contained in this layer, view the Data tab and select "Fields". The following alterations have been made to the tabular data: Joined all tables to create one wide attribute table: P1 - Race P2 - Hispanic or Latino, and not Hispanic or Latino by Race P3 - Race for the Population 18 Years and Over P4 - Hispanic or Latino, and not Hispanic or Latino by Race for the Population 18 Years and Over H1 - Occupancy Status (Housing) P5 - Group Quarters Population by Group Quarters Type (correctional institutions, juvenile facilities, nursing facilities/skilled nursing, college/university student housing, military quarters, etc.) Header After joining, dropped fields: FILEID, STUSAB, CHARITER, CIFSN, LOGRECNO, GEOVAR, GEOCOMP, LSADC, BLOCK, BLKGRP, and TBLKGRP. GEOCOMP was renamed to GEOID and moved be the first column in the table, the original GEOID was dropped. Placeholder fields for future legislative districts have been dropped: CD118, CD119, CD120, CD121, SLDU22, SLDU24, SLDU26, SLDU28, SLDL22, SLDL24 SLDL26, SLDL28. P0020001 was dropped, as it is duplicative of P0010001. Similarly, P0040001 was dropped, as it is duplicative of P0030001. In addition to calculated fields, County_Name and State_Name were added. The following calculated fields have been added (see long field descriptions in the Data tab for formulas used): PCT_P0030001: Percent of Population 18 Years and Over PCT_P0020002: Percent Hispanic or Latino PCT_P0020005: Percent White alone, not Hispanic or Latino PCT_P0020006: Percent Black or African American alone, not Hispanic or Latino PCT_P0020007: Percent American Indian and Alaska Native alone, not Hispanic or Latino PCT_P0020008: Percent Asian alone, Not Hispanic or Latino PCT_P0020009: Percent Native Hawaiian and Other Pacific Islander alone, not Hispanic or Latino PCT_P0020010: Percent Some Other Race alone, not Hispanic or Latino PCT_P0020011: Percent Population of Two or More Races, not Hispanic or Latino PCT_H0010002: Percent of Housing Units that are Occupied PCT_H0010003: Percent of Housing Units that are Vacant Please note these percentages might look strange at the individual tract level, since this data has been protected using differential privacy.* *To protect the privacy and confidentiality of respondents, data has been protected using differential privacy techniques by the U.S. Census Bureau. This means that some individual tracts will have values that are inconsistent or improbable. However, when aggregated up, these issues become minimized. The pop-up on this layer uses Arcade to display aggregated values for the surrounding area rather than values for the tract itself. Download Census redistricting data in this layer as a file geodatabase. Additional links: U.S. Census Bureau U.S. Census Bureau Decennial Census About the 2020 Census 2020 Census 2020 Census data quality Decennial Census P.L. 94-171 Redistricting Data Program本图层包含由美国人口普查局（U.S. Census Bureau）发布的、覆盖全美各州、华盛顿哥伦比亚特区（DC）及波多黎各的2020年十年一次人口普查选区重划数据，数据粒度为普查街区（census tract）。本数据集的属性字段源自2020年《公法94-171》（Public Law 94-171，P.L. 94-171）表格。数据下载日期为2021年8月12日，涉及的普查表格包括P1、P2、P3、P4、H1、P5及表头文件，下载来源为美国人口普查局FTP站点。 数据处理说明：本数据从美国人口普查局FTP站点下载后，导入为SAS格式，并与2020年TIGER/Line地理数据库（2020 TIGER/Line Geodatabases）的边界数据进行关联。所有边界数据已投影至Web Mercator坐标系，各属性均已配置清晰的描述性别名。未对数据顶点进行任何修改，所有属性保留人口普查局规定的原始名称，同时增设了源自普查局官方技术文档的描述性别名与详细说明。如需查看本图层包含的完整属性列表，请切换至「数据」选项卡并选择「字段」。 本图层对表格数据进行了如下处理： 1. 合并所有原始表格以生成一张宽幅属性表，各表格对应主题如下： - P1：种族构成 - P2：西班牙裔或拉丁裔人口及按种族划分的非西班牙裔/拉丁裔人口 - P3：18岁及以上人口种族构成 - P4：18岁及以上人口中西班牙裔或拉丁裔人口及按种族划分的非西班牙裔/拉丁裔人口 - H1：住房居住状态 - P5：按集体居住类型划分的集体宿舍人口（涵盖惩教机构、青少年管教设施、护理院/专业护理机构、高校学生宿舍、军事营房等场景） 2. 合并完成后删除以下字段：FILEID、STUSAB、CHARITER、CIFSN、LOGRECNO、GEOVAR、GEOCOMP、LSADC、BLOCK、BLKGRP及TBLKGRP。 3. 将GEOCOMP字段重命名为GEOID并设为表格首列，同时删除原始GEOID字段。 4. 移除预留未来立法选区的占位符字段：CD118、CD119、CD120、CD121、SLDU22、SLDU24、SLDU26、SLDU28、SLDL22、SLDL24、SLDL26、SLDL28。 5. 删除重复字段：P0020001（与P0010001重复）及P0040001（与P0030001重复）。 6. 除新增计算字段外，补充County_Name（县名）与State_Name（州名）两个字段。 新增计算字段及其含义（详细计算公式请参阅「数据」选项卡中的字段详细说明）： - PCT_P0030001：18岁及以上人口占总人口比例 - PCT_P0020002：西班牙裔或拉丁裔人口占比 - PCT_P0020005：非西班牙裔/拉丁裔白人独居人口占比 - PCT_P0020006：非西班牙裔/拉丁裔黑人或非裔美国人独居人口占比 - PCT_P0020007：非西班牙裔/拉丁裔美洲印第安人与阿拉斯加原住民独居人口占比 - PCT_P0020008：非西班牙裔/拉丁裔亚裔独居人口占比 - PCT_P0020009：非西班牙裔/拉丁裔夏威夷原住民及其他太平洋岛民独居人口占比 - PCT_P0020010：非西班牙裔/拉丁裔其他种族独居人口占比 - PCT_P0020011：非西班牙裔/拉丁裔多种族人口占比 - PCT_H0010002：已占用住房单元占总住房单元比例 - PCT_H0010003：空置住房单元占总住房单元比例 请注意，由于本数据采用差分隐私（differential privacy）技术进行隐私保护，单个普查街区的占比数值可能出现异常。美国人口普查局通过差分隐私技术保护受访者的隐私与机密性，这意味着部分单个普查区域的数值可能存在不一致或不合理的情况，但在汇总至更高行政层级后，此类问题将显著缓解。本图层的弹窗将使用Arcade脚本显示周边区域的汇总值，而非单个普查街区的原始数值。 用户可将本图层的人口普查选区重划数据下载为文件地理数据库（file geodatabase）。 附加链接： - 美国人口普查局（U.S. Census Bureau） - 美国人口普查局十年一次人口普查 - 2020年人口普查简介 - 2020年人口普查 - 2020年人口普查数据质量 - 十年一次人口普查P.L. 94-171选区重划数据项目