American Time Use Survey: Concepts
The major purpose of the American Time Use Survey (ATUS) is to develop nationally representative estimates of how people spend their time. The survey was developed in the late 1990s and early 2000s as a way to measure the amount of time Americans spend doing unpaid, nonmarket work, such as unpaid childcare, eldercare, housework, and volunteering. The survey also provides information on the amount of time people spend in many other activities, such as paid work, religious activities, socializing, exercising, and relaxing. To collect this information, interviewers ask each respondent to recall their activities over a full 24-hour day, beginning at 4 a.m. on the day prior to the interview and ending at 4 a.m. on the day of the interview. Interviews are conducted nearly every day of the year by U.S. Census Bureau interviewers using computer assisted telephone interview technology. Interviewers ask respondents to report every activity they took part in during that 24-hour period, including where they were and whom they were with for most activities. Additional information, such as whether an activity was done for one's job or business, also is collected. After the interview is completed, each activity is assigned a six-digit code according to the activity classification system described in the subsection “Activity Definitions.” Annual data are available beginning with 2003.
The next two sections provide definitions of terms related to ATUS operations and estimation, and definitions of the ATUS major activity categories. ATUS industry codes use the Census Bureau’s Industry Classification System, and ATUS occupation codes use the Census Bureau’s Occupation Classification System; for more information on these codes, see Occupation and Industry Codes in the American Time Use Survey.
Terms related to operations and estimation
The key concepts and definitions that follow are used to create ATUS estimates and publications. For a complete list, see the Concepts and Definitions section of the American Time Use Survey User’s Guide.
Average day. The average-day measure reflects an average distribution across all people in the reference population and all days of the week.
Average hours per day. The average number of hours spent in a 24-hour day (between 4 a.m. on the diary day and 4 a.m. on the interview day) doing a specified activity.
Condition related to aging. An ongoing ailment or physical or emotional limitation that typically affects older people, such as becoming more frail; having difficulty seeing, hearing, or physically moving; becoming more forgetful; tiring more quickly; or having specific medical ailments that are more common among older adults. The term also refers to existing conditions that become progressively worse as one ages.
Day of the week. Estimates of time spent in activities on weekdays are an average of reports about Monday through Friday, excluding major weekday holidays. Estimates of time spent in activities on weekend days and holidays are an average of reports about Saturdays, Sundays, and the following holidays: New Year’s Day, Easter, Memorial Day, the Fourth of July, Labor Day, Thanksgiving Day, and Christmas Day.
Designated day. The day of the week on which a designated person will be called for an interview. For example, a person with a designated day of Tuesday will be called for up to eight consecutive Tuesdays to secure one interview about what she did on Monday.
Designated person. A person selected to participate in ATUS.
Diary day. The diary day is the day about which the designated person reports. For example, the diary day of a designated person interviewed on Tuesday is Monday. Diary days are assigned, and designated individuals may not substitute another day of the week on which to report.
Eldercare. Eldercare consists of providing unpaid care or assistance to an individual who needed help because of a condition related to aging. This care can be provided by a family member or a non-family member. Care can be provided in the recipient’s home, the provider’s home, or a care facility, such as a nursing home. Eldercare can involve a range of care activities, such as assisting with grooming and feeding, preparing meals, arranging medical care, and providing transportation. Eldercare can also involve providing companionship or being available to assist when help is needed; thus, it can be associated with nearly any activity.
Eldercare provider. Someone who provided eldercare more than one time in the 3 to 4 months prior to the interview day.
Employed. All persons who:
1. At any time during the 7 days prior to the interview did any work at all as paid employees; worked in their own business or profession or on their own farm; or
2. Were not working during the seven days prior to the interview but had jobs or businesses from which they were temporarily absent because of illness, bad weather, vacation, childcare problems, labor-management disputes, maternity or paternity leave, job training, or other family or personal reasons, whether or not they were paid for the time off or were seeking other jobs; or
3. Usually worked 15 or more hours as unpaid workers in a family-operated enterprise.
Employed full time. Full-time workers are those who usually worked 35 or more hours per week at all jobs combined.
Employed part time. Part-time workers are those who usually worked fewer than 35 hours per week at all jobs combined.
Not employed. People are not employed if they do not meet the conditions for employment. People who are not employed include those classified as unemployed as well as those classified as not in the labor force (as defined in the Current Population Survey).
Household children. These are children under age 18 residing in the household of the ATUS respondent. The children may be related to the respondent (such as their own children, grandchildren, nieces or nephews, or brothers or sisters) or not related (such as foster children or children of roommates or boarders).
Own children. The respondent’s own children, whether they live in the respondent’s household or in another household. Biological, step-, and adopted children are considered own children; foster children are not.
Population measures. These estimates refer to all people having a quality or characteristic in common. Estimates that refer to a population—such as all people or all employed people—account for every respondent in the population. Population estimates about an activity include all people, even those who did not engage in a specified activity on the diary day. For example, the population measure average hours per day that employed people worked includes all employed people and is an average of the days they did and the days they did not work.
Participant measures. These estimates refer only to individuals who engaged in a particular activity on the diary day. For example, the participant measure average hours per day that employed people worked on days they worked is an average for employed people on days they spent time working.
Primary activity. A primary activity is the main activity a respondent was doing at a specified time.
Secondary activities. A secondary (or simultaneous) activity is an activity done at the same time as a primary activity. With the exception of the care of children under age 13, information on secondary activities is not collected in ATUS.
Secondary childcare. Secondary childcare is care for children under age 13 that is done while doing something else as a primary activity, such as cooking dinner. Secondary childcare estimates are derived by summing the durations of activities during which respondents had at least one child under age 13 in their care while doing other things. The time individuals spend providing secondary childcare to household children is further restricted to the time between when the first household child under age 13 woke up and when the last household child under 13 went to bed. It is also restricted to times the respondent was awake. If respondents report providing both primary and secondary care at the same time, the time is attributed to primary care only.
ATUS uses a unique activity classification system to categorize the different primary activities respondents engage in throughout the course of a day. The ATUS coding lexicon uses a 3-tiered system, with 17 major, or first-tier, categories, each having 2 additional levels of detail. Descriptions of each of the major lexicon activity categories follow.
Further details on the structure of ATUS activity categories are presented in the next section, Data sources. Complete single-year and multiyear coding lexicons are available in PDF and Excel formats at www.bls.gov/tus/lexicons.htm.
Caring for and helping household members. Time spent doing activities to care for or help any child (under age 18) or adult in the household, regardless of the person’s relationship to the survey respondent or the physical or mental health status of the person being helped, is classified here. Caring and helping activities for household children and adults are coded separately in subcategories.
Primary childcare activities include time spent providing physical care; playing with children; reading with children; assistance with homework; attending children’s events; taking care of children’s health care needs; and dropping off, picking up, and waiting for children. Passive childcare done as a primary activity (such as “keeping an eye on my son while he swam in the pool”) also is included. A child’s presence during the activity is not enough by itself to classify the activity as childcare. For example, “watching television with my child” is coded as a leisure activity, not childcare.
Caring for and helping household members also includes a range of activities done to benefit adult members of households, such as providing physical and medical care or obtaining medical services. Doing something as a favor for or helping another household adult does not automatically result in classification as a helping activity. For example, a report of “helping my spouse cook dinner” is considered a household activity (food preparation), not a helping activity, because cooking dinner benefits the household as a whole. By contrast, doing paperwork for another person usually benefits the individual, so a report of “filling out an insurance application for my spouse” is considered a helping activity.
Caring for and helping nonhousehold members. This category includes time spent in activities done to care for or help others—both children (under age 18) and adults—who do not live in the household. When done for or through an organization, time spent helping nonhousehold members is classified as volunteering rather than as helping nonhousehold members. Care of nonhousehold children, even when done as a favor or helping activity for another adult, is always classified as caring for and helping nonhousehold children, not as helping another adult.
Purchasing goods and services. This category includes time spent purchasing consumer goods, professional and personal care services, household services, and government services. Consumer purchases include most purchases and rentals of consumer goods, regardless of the mode or place of purchase or rental (in person, online, via telephone, at home, or in a store). Gasoline, grocery, other food purchases, and all other shopping are further broken out in subcategories.
Eating and drinking. All time spent eating or drinking (except that done as part of a work or volunteer activity), whether alone, with others, at home, at a place of purchase, or somewhere else, is classified as eating and drinking. Time spent purchasing, or talking related to purchasing, meals, snacks, and beverages is not counted as part of this category but is counted instead as time spent making consumer purchases.
Educational activities. Time spent taking classes for a degree or for personal interest (including taking Internet or other distance‑learning courses), time spent doing research and homework, and time spent taking care of administrative tasks related to education (such as registering for classes or obtaining a school ID) are included in this category. For high school students, before‑school and afterschool extracurricular activities (except sports) also are classified as educational activities. Educational activities do not include time spent for classes or training received as part of a job. Time spent helping others with their education-related activities is classified as an activity involving caring for and helping others.
Government services and civic obligations. This category captures time spent obtaining and using government services (police, fire, social services), such as applying for welfare, and time spent purchasing government-required licenses or paying fines or fees. Civic obligations include government-required duties—such as serving on a jury or appearing in court—as well as activities that assist or influence government processes, such as voting and attending town hall meetings.
Household activities. Household activities are activities done by people to maintain their households. This category includes time spent in housework; cooking; lawn and garden care; pet care; vehicle maintenance and repair; home maintenance, repair, decoration, and renovation; and household management and organizational activities (such as filling out paperwork, balancing a checkbook, and planning a party). Food preparation, whether or not reported as done specifically for another household member, is always classified as a household activity, unless it was done as a volunteer, work, or income-generating activity. For example, “making breakfast for my son” is coded as a household activity, not as childcare.
Household services. Time spent arranging for and purchasing household services provided by someone else for pay is classified here. Household services include housecleaning; cooking; lawn care and landscaping; pet care; tailoring, laundering, and drycleaning; vehicle maintenance and repairs; and home repairs, maintenance, and construction.
Personal care. Personal care activities include sleeping, grooming (such as bathing or dressing), health-related self-care, and personal or private activities. Receiving unpaid personal care from others (e.g., “my sister put polish on my nails”) also is captured in this category.
Professional and personal care services. Time spent obtaining, receiving, and purchasing professional and personal care services provided by someone else for pay is classified into this category. Professional services include childcare, financial services and banking, legal services, medical and adult care services, real estate services, and veterinary services. Personal care services include services received from day spas, hair salons and barbershops, nail salons, and tanning salons. Activities classified here include time spent paying, meeting with, or talking to service providers, as well as time spent receiving the service or waiting to receive the service.
Religious and spiritual activities. Religious activities include activities normally associated with membership in or identification with specific religions or denominations, such as attending religious services; participating in choirs, youth groups, orchestras, or unpaid teaching (unless identified as volunteer activities); and engaging in personal religious practices, such as praying.
Socializing, relaxing, and leisure. This category includes face-to-face social communication and hosting or attending social functions. Time spent communicating with others via telephone calls, texting, mail, or email is not part of the category. Leisure activities include watching television; reading; relaxing or thinking; playing computer, board, or card games; using a computer or the Internet for personal interest; playing or listening to music; and other activities, such as attending arts, cultural, and entertainment events.
Sports, exercise, and recreation. Participating in—as well as attending or watching—sports, exercise, and recreational activities, whether team or individual and competitive or noncompetitive, falls into this category. Recreational activities include yard games like croquet and horseshoes, as well as activities like billiards and dancing.
Telephone calls. This category captures time spent in telephone communication; it also includes texting and Internet voice and video calling. Telephone and Internet purchases of consumer goods are classified into the category of consumer purchases. Telephone calls identified as related to work or volunteering are classified as either work or volunteering.
Traveling. Nearly all time spent traveling is classified here. When a respondent reports doing another activity while traveling—for example, eating breakfast while riding the bus to work—the travel activity is recorded as the main activity. Walking and biking are considered traveling when they are used to get from one destination (an address or a building) to another, but not when the primary purpose is exercise. Travel done as an essential part of one’s job—for example, driving a taxi—is recorded as work, not travel. Exhibit 5.1 in the ATUS User’s Guide has examples of how travel activities are classified; typically, they are dependent upon the activities that immediately follow and precede them.
Volunteer activities. This category captures time spent volunteering for or through an organization.
Working and work-related activities. This category includes time spent working, doing activities as part of one’s job, engaging in income-generating activities not as part of one’s job, and job search activities. “Working” includes hours spent doing the specific tasks required of one’s main or other job, regardless of the location or time of day. “Work-related activities” include activities that are not obviously work but are done as part of one’s job, such as having a business lunch and playing golf with clients. “Other income-generating activities” are those done “on the side” or under an informal arrangement and are not part of a regular job. Such activities might include selling homemade crafts, babysitting, maintaining a rental property, or having a yard sale. These activities are those for which people are paid or will be paid.
Statistics based on the ATUS are subject to both sampling error and nonsampling error. When a sample, rather than an entire population, is surveyed, estimates 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.
Sample estimates from a given survey design are unbiased when an average of the estimates from all possible samples would yield, hypothetically, the true population value. In this case, the sample estimate and its standard error can be used to construct approximate confidence intervals, or ranges of values that include the true population value accompanied by known probabilities. If the process of selecting a sample from the population were repeated many times, an estimate made from each sample, and a suitable estimate of its standard error calculated for each sample, then approximately 90 percent of the intervals from 1.645 standard errors below the estimate to 1.645 standard errors above the estimate would include the true population value.
The ATUS data also are affected by nonsampling error, which is the average difference between population and sample values for samples generated by a given process. Nonsampling error can occur for many reasons, including the failure to sample a segment of the population, inability to obtain information from 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. Nonsampling error can also occur if nonresponse is correlated with time use. The average annual response rates for the ATUS can be found in chapter 3.6 of the ATUS User’s Guide. The ATUS statistical weights in part adjust for nonsampling error, and quality assurance procedures are used to minimize nonsampling, data entry, and coding errors in the survey estimates.
Although attempts have been made to collect the most accurate data possible, the ATUS data do have limitations. For example, with the exception of childcare, information on secondary activities (activities that are done at the same time as the primary activity) is not collected. This decision not to collect such information could lead to underestimates of the amount of time people spend doing activities that are frequently done in combination with other activities. For instance, ATUS estimates likely underestimate the amount of time people spend listening to music, because so many people listen to music while doing other things.
Estimates appearing in ATUS tables must meet reliability standards before being presented to the public. In 2010, a new standard was developed that takes into account the coefficient of variation, standard error, and number of observations available before reporting an estimate. Prior to 2010, a standard was in place that included only the sample size or population base for the estimate.
Beginning with 2010 data, ATUS estimates of average hours per day and participation rates are not published unless there are a minimum number of respondents representing the given population. Additional publication criteria are applied that include the number of respondents who reported doing a specified activity and the standard error or coefficient of variation for the estimate. Estimates that are considered “close to zero” or that round to zero (e.g., 0.00 for estimates of hours) are published as approximately zero, or “~0.”
Chapter 10 of the User’s Guide has additional information on ATUS data quality. For a detailed description of the statistical reliability criteria necessary for publication, please email the ATUS staff at ATUSinfo@bls.gov.
Last Modified Date: October 17, 2019