ACS Employment Status Variables - Tract

This layer shows hours worked, and those unemployed and not in labor force. This is shown by tract, county, and state boundaries. This service is updated annually to contain the most currently released American Community Survey (ACS) 5-year data, and contains estimates and margins of error. There are also additional calculated attributes related to this topic, which can be mapped or used within analysis. This layer is symbolized to show the percentage of unemployed population within the civilian labor force. To see the full list of attributes available in this service, go to the "Data" tab, and choose "Fields" at the top right. Current Vintage: 2015-2019 ACS Table(s): B23020, B23025 Data downloaded from: Census Bureau's API for American Community Survey Date of API call: December 10, 2020 National Figures: data.census.gov The United States Census Bureau's American Community Survey (ACS): About the Survey Geography & ACS Technical Documentation News & Updates This ready-to-use layer can be used within ArcGIS Pro, ArcGIS Online, its configurable apps, dashboards, Story Maps, custom apps, and mobile apps. Data can also be exported for offline workflows. For more information about ACS layers, visit the FAQ. Please cite the Census and ACS when using this data. Data Note from the Census: Data are based on a sample and are subject to sampling variability. The degree of uncertainty for an estimate arising from sampling variability is represented through the use of a margin of error. The value shown here is the 90 percent margin of error. The margin of error can be interpreted as providing a 90 percent probability that the interval defined by the estimate minus the margin of error and the estimate plus the margin of error (the lower and upper confidence bounds) contains the true value. In addition to sampling variability, the ACS estimates are subject to nonsampling error (for a discussion of nonsampling variability, see Accuracy of the Data). The effect of nonsampling error is not represented in these tables. Data Processing Notes: This layer is updated automatically when the most current vintage of ACS data is released each year, usually in December. The layer always contains the latest available ACS 5-year estimates. It is updated annually within days of the Census Bureau's release schedule. Click here to learn more about ACS data releases. Boundaries come from the US Census TIGER geodatabases. Boundaries are updated at the same time as the data updates (annually), and the boundary vintage appropriately matches the data vintage as specified by the Census. These are Census boundaries with water and/or coastlines clipped for cartographic purposes. For census tracts, the water cutouts are derived from a subset of the 2010 AWATER (Area Water) boundaries offered by TIGER. For state and county boundaries, the water and coastlines are derived from the coastlines of the 500k TIGER Cartographic Boundary Shapefiles. The original AWATER and ALAND fields are still available as attributes within the data table (units are square meters). The States layer contains 52 records - all US states, Washington D.C., and Puerto Rico Census tracts with no population that occur in areas of water, such as oceans, are removed from this data service (Census Tracts beginning with 99). Percentages and derived counts, and associated margins of error, are calculated values (that can be identified by the "_calc_" stub in the field name), and abide by the specifications defined by the American Community Survey. Field alias names were created based on the Table Shells file available from the American Community Survey Summary File Documentation page. Negative values (e.g., -4444...) have been set to null, with the exception of -5555... which has been set to zero. These negative values exist in the raw API data to indicate the following situations: The margin of error column indicates that either no sample observations or too few sample observations were available to compute a standard error and thus the margin of error. A statistical test is not appropriate. Either no sample observations or too few sample observations were available to compute an estimate, or a ratio of medians cannot be calculated because one or both of the median estimates falls in the lowest interval or upper interval of an open-ended distribution. The median falls in the lowest interval of an open-ended distribution, or in the upper interval of an open-ended distribution. A statistical test is not appropriate. The estimate is controlled. A statistical test for sampling variability is not appropriate. The data for this geographic area cannot be displayed because the number of sample cases is too small.

本图层展示了工作时长、失业人口及非劳动力人口分布，以普查区（census tract）、县及州界为统计单元。本服务每年更新，纳入最新发布的美国社区调查（American Community Survey, ACS）5年期数据，包含各类估计值与误差边际。此外还包含与该主题相关的额外计算属性，可用于制图或分析工作。本图层的符号系统用于展示民用劳动力中失业人口占比。若需查看本服务中可用属性的完整列表，请前往"数据"选项卡，并选择右上角的"字段"菜单。当前数据期：2015-2019年ACS数据表B23020、B23025。数据下载来源：美国人口普查局美国社区调查API。API调用日期：2020年12月10日。全国统计数据来源：data.census.gov。美国人口普查局美国社区调查（ACS）：调查简介、地理分区与ACS技术文档、最新动态。本图层为即用型数据，可在ArcGIS Pro、ArcGIS Online及其可配置应用、仪表板、Story Maps、自定义应用与移动应用中使用。数据亦可导出用于离线作业流程。如需了解更多ACS图层相关信息，请访问常见问题解答（FAQ）页面。使用本数据时，请注明美国人口普查局与ACS来源。美国人口普查局数据说明：本数据基于抽样调查，存在抽样变异性。抽样变异性带来的估计值不确定程度通过误差边际（margin of error）体现。此处展示的为90%置信水平的误差边际，其含义为：估计值加减误差边际所构成的区间（即置信上下限）有90%的概率包含真实数值。除抽样变异性外，ACS估计值还存在非抽样误差（相关讨论详见《数据准确性》一文），但本表格未体现非抽样误差的影响。数据处理说明：本图层会在每年最新一期ACS数据发布时自动更新，通常更新时间为12月。本图层始终包含最新可用的ACS 5年期估计值，每年会在美国人口普查局发布数据后的数日内完成更新。点击此处可了解更多ACS数据发布相关信息。地理边界数据源自美国人口普查局TIGER地理数据库（TIGER geodatabases）。边界数据会与统计数据同步每年更新，且边界数据的期次与人口普查局指定的数据期次完全匹配。为满足制图需求，本数据已对普查边界中的水体及海岸线进行裁切处理：对于普查区，水体裁切范围源自TIGER提供的2010年AWATER（水域面积）边界子集；对于州与县界，水体及海岸线源自50万比例尺TIGER制图边界Shapefile。原始AWATER与ALAND字段仍可作为数据表格中的属性使用（单位：平方米）。州级图层共包含52条记录，涵盖全美所有州、华盛顿哥伦比亚特区及波多黎各。本数据服务已移除海洋等水域区域内无人口的普查区（即以99开头的普查区）。各类占比、衍生计数及对应的误差边际均为计算所得值（可通过字段名中的"_calc_"标识识别），且严格遵循美国社区调查的相关规范。字段别名均基于美国社区调查汇总文件文档页面提供的表框架（Table Shells）文件生成。除-5555…已被设置为0外，其余负值（如-4444…）均已被设置为空值。原始API数据中的此类负值用于表示以下场景：1. 误差边际列提示：无可用样本观测值或样本观测值过少，无法计算标准误及误差边际，不适用于统计检验；2. 无可用样本观测值或样本观测值过少，无法计算估计值；或因其中一个或两个中位数估计值落在开放式分布的最低区间或最高区间内，无法计算中位数比值；3. 中位数落在开放式分布的最低区间或最高区间内；4. 不适用于统计检验；5. 估计值已受控；6. 不适用于抽样变异性的统计检验；7. 样本案例数量过少，无法展示该地理区域的数据。