Technical Note The data presented in this news release were collected through a supplement to the May and September 2018 Current Population Survey (CPS). The CPS is a monthly survey of about 60,000 eligible households that provides data on employment and unemployment for the nation’s civilian noninstitutional population age 16 and over. The CPS is conducted by the U.S. Census Bureau for the Bureau of Labor Statistics (BLS). The U.S. Department of Labor’s Chief Evaluation Office sponsored the collection of the May and September 2018 supplement to obtain information about the number and characteristics of those who do and do not file for unemployment insurance (UI) benefits, as well as information on those who receive benefits. These data provide information not available from the UI program administrative data or the monthly CPS. One of the most persistent misconceptions about the CPS unemployment measure is that it is based on the number of people who apply for or receive UI benefits. However, data on UI program participation cannot be used to determine unemployment because the CPS concept includes people who are not eligible for benefits, who have exhausted their benefits, and who do not apply for benefits. The monthly CPS does not include questions about UI participation. Only people who have previously worked are eligible for UI benefits, and they generally must apply shortly after their last job. Therefore, estimates presented in this news release are restricted to people who had worked at some point in the 12 months prior to the survey. In 2018, nearly two-thirds of the unemployed had worked in the last 12 months. Other unemployed people, including those who entered the labor force for the first time and those who last worked more than a year ago, are excluded from this news release. The estimates in this release--referred to as 2018 estimates--are averages of data collected in May and September 2018. Data are weighted to produce nationally representative estimates. The supplement weights are controlled to population estimates that are averaged over the 2 months. Information in this news release will be made available to sensory-impaired individuals upon request. Voice phone: (202) 691-5200; Federal Relay Service: (800) 877-8339. Definitions The principle definitions used in this news release are described below. Additional information about CPS concepts and definitions is available on the BLS website at www.digitalmonojit.com/cps/definitions.htm. Unemployed who worked in the past 12 months. In the CPS, people are classified as unemployed if they were not employed during the survey reference week; were available for work during the survey reference week (except for temporary illness); and had made at least one specific, active effort to find employment sometime during the 4-week period ending with the survey reference week. People who were waiting to be recalled to a job from which they had been laid off need not have been looking for work to be classified as unemployed. Data in this news release exclude unemployed people with no previous work experience and those who last worked more than 12 months prior to the survey. However, all unemployed persons expecting to be recalled from temporary layoff are included, regardless of whether they worked in the 12 months prior to the survey. Marginally attached to the labor force who worked in the past 12 months. People marginally attached to the labor force are those who are neither employed nor unemployed, who want a job, have searched for work during the prior 12 months, and were available to take a job during the survey reference week, but had not looked for work in the 4-week period ending with the survey reference week. If they had looked for work in the 4-week period, they would be counted as unemployed. Data in this news release on people marginally attached to the labor force refer to those who worked in the past 12 months, a subset of total marginally attached. Unemployment Insurance (UI). The federal-state UI program provides unemployment benefits to eligible workers (as determined under state law). The UI payments (benefits) are intended to provide temporary financial assistance to unemployed workers. Each state administers a separate UI program within guidelines established by federal law. Eligibility for UI benefit amounts and the length of time benefits are available are determined by the state law under which UI claims are established. For more information about state UI programs, visit https://oui.doleta.gov/unemploy/uifactsheet.asp. UI benefit applicants. In the CPS, UI applicants are people who applied for UI benefits since their last job. Whether a person applied for UI benefits was determined through answers to the question: “Have you applied for unemployment benefits since your last job?? Data in this news release refer to unemployed individuals and people marginally attached to the labor force who had worked in the past 12 months. UI benefit recipients. In the CPS, these individuals are UI applicants who received UI benefits since their last job. This information was obtained from the following question: “Have you received any unemployment benefits since your last job??This question was asked of people who had applied for UI benefits since their last job. Data in this news release refer to unemployed individuals and people marginally attached to the labor force who had worked in the past 12 months. Union coverage on last job. Data in this news release refer both to union members and to those who were covered by a union contract on their last job. Union coverage on the last job is based on the question: “Were you a union member or covered by a union contract on your last job?? Main reason for not applying for UI benefits. This information is based on responses to the question: “There are a variety of reasons why people might not apply for unemployment benefits. What are the reasons you have not applied for unemployment benefits since your last job??Interviewers could record more than one reason. If respondents provided more than one reason, interviewers asked which was their main reason. Comparability of the estimates Previous supplements collected data on UI applicants and benefit recipients in 2005, 1993, 1989, and 1976. The 2018 supplement questions used to identify UI applicants and benefit recipients were similar to the 2005 supplement but were different from questions used in earlier years. The 2018 estimates are not strictly comparable with those from prior years. Changes in survey methods affect the comparability of estimates over time. For example, the questions were not the same in all supplements. Also, collection periods differed across supplements, and the supplements were not always administered to all CPS respondents. For example, the 2018 supplement was collected in 2 nonconsecutive months (May and September) from the full CPS sample. The supplements for 2005, 1993, and 1989 were collected in 4 different months, and the questions were asked of about one-fourth of the CPS sample (the outgoing rotations). (Specifically, the 2005 supplement data were collected in January, May, July, and November; the 1993 supplement was administered in February, June, August, and November; and the 1989 supplement was conducted in May, August, and November 1989 and in February 1990.) The 1976 supplement was administered to the full sample in May 1976. Other factors should also be considered when analyzing the data. Different points in the business cycle, changes in state UI laws, and the seasonal nature of applying for UI benefits can further complicate comparisons of data over time. For example, the unemployment rate in 2018 was relatively low by historical standards, which may impact the number and characteristics of people who apply for UI benefits. Reliability of the estimates Statistics based on the CPS are subject to both sampling and nonsampling error. When a sample, rather than the entire population, is surveyed, there is a chance that the sample estimates may differ from the true population values they represent. The component of this difference that occurs because samples differ by chance is known as sampling error, and its variability is measured by the standard error of the estimate. There is about a 90-percent chance, or level of confidence, that an estimate based on a sample will differ by no more than 1.6 standard errors from the true population value because of sampling error. BLS analyses are generally conducted at the 90-percent level of confidence. The CPS data also are affected by nonsampling error. Nonsampling error can occur for many reasons, including the failure to sample a segment of the population, inability to obtain information for all respondents in the sample, inability or unwillingness of respondents to provide correct information, and errors made in the collection or processing of the data. General information about the reliability of data from the CPS is available at www.digitalmonojit.com/cps/documentation.htm#reliability.