USA Census 2020 Redistricting - Tract

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、覆盖全美各州及华盛顿哥伦比亚特区（DC）与波多黎各的2020年十年一次人口普查选区重划数据，数据粒度为普查地段（census tract）。这些属性字段源自2020年《公法94-171》（Public Law 94-171，P.L. 94-171）附表。数据下载日期：2021年8月12日；所用普查附表包括P1、P2、P3、P4、H1、P5及表头文件；数据下载自美国人口普查局FTP站点。 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边界数据进行关联。边界数据源自2020年TIGER/Line地理数据库（TIGER/Line Geodatabases），已被投影至Web Mercator坐标系；每个属性字段均已配置清晰的描述性别名。数据顶点未做任何修改，所有属性字段均保留美国人口普查局指定的原始名称，同时添加了源自该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属性字段详细列表，请切换至「数据」选项卡并选择「字段」。 对表格数据执行了以下处理：将所有附表合并为一张宽属性表，各附表说明如下：P1：种族；P2：西班牙裔/拉丁裔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岁及以上人口的西班牙裔/拉丁裔及按种族划分的非西班牙裔/拉丁裔人口；H1：住房占用状态；P5：按居住类型划分的集体宿舍人口（包括惩教机构、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）；表头文件。 合并完成后，删除了以下字段：FILEID、STUSAB、CHARITER、CIFSN、LOGRECNO、GEOVAR、GEOCOMP、LSADC、BLOCK、BLKGRP及TBLKGRP。将GEOCOMP重命名为GEOID，并将其设为表格的第一列，同时删除原始GEOID字段。删除了预留的未来立法选区占位字段：CD118、CD119、CD120、CD121、SLDU22、SLDU24、SLDU26、SLDU28、SLDL22、SLDL24、SLDL26及SLDL28。P0020001因与P0010001重复而被删除；同理，P0040001因与P0030001重复而被删除。除计算字段外，还新增了县名（County_Name）与州名（State_Name）字段。 新增了以下计算字段（所用计算公式详见「数据」选项卡中的字段详细说明）： PCT_P0030001：18岁及以上人口占比 PCT_P0020002：西班牙裔/拉丁裔人口占比 PCT_P0020005：非西班牙裔/拉丁裔白人单独占比 PCT_P0020006：非西班牙裔/拉丁裔黑人或非裔美国人单独占比 PCT_P0020007：非西班牙裔/拉丁裔美国印第安人与阿拉斯加原住民单独占比 PCT_P0020008：非西班牙裔/拉丁裔亚裔单独占比 PCT_P0020009：非西班牙裔/拉丁裔夏威夷原住民及其他太平洋岛民单独占比 PCT_P0020010：非西班牙裔/拉丁裔其他单独种族人口占比 PCT_P0020011：非西班牙裔/拉丁裔多种族人口占比 PCT_H0010002：已占用住房单元占比 PCT_H0010003：空置住房单元占比 请注意，由于本数据采用差分隐私（differential privacy）技术进行保护，单个普查地段的占比数值可能存在异常。*为保护受访者的隐私与机密性，美国人口普查局已通过差分隐私技术对数据进行处理，这意味着部分单个普查地段的数值可能存在不一致或不合理的情况，但在聚合至更高层级后，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聚合数值，而非单个普查地段的原始数值。 可将本图层中的人口普查选区重划数据下载为文件地理数据库（file geodatabase）。相关链接：美国人口普查局、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。