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Quarterly Services

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Quarterly Services Survey FAQs

What is seasonal adjustment?

Seasonal adjustment is the process of estimating and removing seasonal effects from a time series in order to better reveal certain non-seasonal features. An example of a seasonal effect is an increase in accounting services during the tax season. (Seasonal effects are defined more precisely below.)

Why do you seasonally adjust data?

Seasonal movements are often large enough that they mask other characteristics of the data that are of interest to analysts who track current economic trends. For example, if each quarter has a different seasonal tendency toward high or low values it can be difficult to detect the general direction of a time series' recent quarterly movement (increase, decrease, turning point, no change, consistency with another economic indicator, etc.). Seasonal adjustment produces data in which the values of neighboring quarters are usually easier to compare. Many data users prefer seasonally adjusted data because they want to see those characteristics that seasonal movements tend to mask, especially changes in the direction of the series.

What kinds of seasonal effects are removed during seasonal adjustment?

Seasonal adjustment procedures remove quarterly time series estimate effects that occur in the same calendar quarter with similar magnitude and direction from year to year. Examples of these effects include economic activity tied to the tax season or to the travel season. The seasonal factors are estimates of average effects for each quarter. It is important to note that seasonal factors are based on present and past experience and that future data may show a different pattern of seasonal factors.

How do you determine which series to seasonally adjust?

Every not seasonally adjusted series published in the Quarterly Services Report is tested for seasonality using X-13ARIMA-SEATS. Series which test positively for seasonality, i.e., show indications of seasonal behavior, are identified as potentially eligible for seasonal adjustment. Diagnostics used to determine which series to seasonally adjust can be found here.

How is the seasonal adjustment derived?

We use X-13ARIMA-SEATS to derive our seasonal adjustment and produce seasonal factors. X-13ARIMA-SEATS is a seasonal adjustment program developed at the U.S. Census Bureau in collaboration with the Bank of Spain that provides both X-11 method seasonal adjustments and ARIMA model-based seasonal adjustments and diagnostics.

QSS estimates are adjusted using the X-11 filter-based adjustment procedure. QSS is currently using version 1.1, build 59 of X-13ARIMA-SEATS.

Which QSS series are seasonally adjusted?

The revenue series for the following NAICS codes are seasonally adjusted:

Selected Services Total
22          Utilities
2211      Electric power generation, transmission and distribution
2212      Natural gas distribution
2213      Water, sewage and other systems
48-49     Transportation and warehousing
481        Air transportation
483        Water transportation
4831      Deep sea, coastal, and Great Lakes water transportation
484        Truck transportation
4841      General freight trucking
48412    General freight trucking, long-distance
4842      Specialized freight trucking
485        Transit and ground passenger transportation
486        Pipeline transportation
487        Scenic and sightseeing transportation
488        Support activities for transportation
492        Couriers and messengers
51          Information
511        Publishing industries (except Internet)
5111      Newspaper, periodical, book, and directory publishers
51111    Newspaper publishers
51112    Periodical publishers
5111 pt  Book, directory and mailing list, and other publishers
5112      Software publishers
512        Motion picture and sound recording industries
515        Broadcasting (except Internet)
5151      Radio and television broadcasting
5152      Cable and other subscription programming
5171      Wired telecommunications carriers
5172      Wireless telecommunications carriers (except satellite)
518        Data processing, hosting, and related services
519        Other information services
522        Credit intermediation and related activities
5221      Depository credit intermediation
5223      Activities related to credit intermediation
53          Real estate and rental and leasing
531        Real estate
5311      Lessors of real estate
5312      Offices of real estate agents and brokers
5313      Activities related to real estate
532        Rental and leasing services
5321      Automotive equipment rental and leasing
53211    Passenger car rental and leasing
53212    Truck, utility trailer, and RV (recreational vehicle) rental and leasing
5324      Commercial and industrial machinery and equipment rental and leasing
533        Lessors of nonfinancial intangible assets (except copyrighted works)
54          Professional, scientific, and technical services
5411      Legal services
5412      Accounting, tax preparation, bookkeeping, and payroll services
5413      Architectural, engineering, and related services
54133    Engineering services
5415      Computer systems design and related services
5416      Management, scientific, and technical consulting services
5417      Scientific research and development services
5418      Advertising, public relations, and related services
5419      Other professional, scientific, and technical services
56          Administrative and support and waste management and remediation services
561        Administrative and support services
5613      Employment services
5615      Travel arrangement and reservation services
561 pt    Other administrative and support services
562        Waste management and remediation services
61          Educational services
6116      Other schools and instruction
6117      Educational support services
62          Health care and social assistance
62          Health care and social assistance - tax-exempt
621        Ambulatory health care services
621        Ambulatory health care services - taxable
621        Ambulatory health care services - tax-exempt
6211      Offices of physicians - taxable
6212      Offices of dentists - taxable
6213      Offices of other health practitioners - taxable
6214      Outpatient care centers
6214      Outpatient care centers - taxable
6214      Outpatient care centers - tax-exempt
6215      Medical and diagnostic laboratories - taxable
6216      Home health care services
6216      Home health care services - taxable
6216      Home health care services - tax-exempt
622        Hospitals
622        Hospitals - taxable
622        Hospitals - tax-exempt
6221      General medical and surgical hospitals
6221      General medical and surgical hospitals - taxable
6221      General medical and surgical hospitals - tax-exempt
6222      Psychiatric and substance abuse hospitals
6222      Psychiatric and substance abuse hospitals - taxable
6222      Psychiatric and substance abuse hospitals - tax-exempt
623        Nursing and residential care facilities
623        Nursing and residential care facilities - tax-exempt
624        Social assistance - taxable
624        Social assistance - tax-exempt
6241      Individual and family services
6242      Community food and housing, and emergency and other relief services
6244      Child day care services
6244      Child day care services - taxable
6244      Child day care services - tax-exempt
71          Arts, entertainment, and recreation
71          Arts, entertainment, and recreation - taxable
71          Arts, entertainment, and recreation - tax-exempt
711        Performing arts, spectator sports, and related industries
711        Performing arts, spectator sports, and related industries - taxable
7111      Performing arts companies
7111      Performing arts companies - taxable
7111      Performing arts companies - tax-exempt
7112      Spectator sports - taxable
7113      Promoters of performing arts, sports, and similar events
7113      Promoters of performing arts, sports, and similar events - taxable
7114      Agents and managers of artist, athletes, entertainers, and other public figures - taxable
7115      Independent artists, writers, and performers - taxable
712        Museums, historical sites, and similar institutions
712        Museums, historical sites, and similar institutions - tax-exempt
713        Amusement, gambling, and recreational industries
713        Amusement, gambling, and recreational industries - taxable
713        Amusement, gambling, and recreational industries - tax-exempt
7131      Amusement parks and arcades - taxable
7132      Gambling industries - taxable
7139      Other amusement and recreation industries
7139      Other amusement and recreation industries - taxable
7139      Other amusement and recreation industries - tax-exempt
721        Accommodation
7211      Traveler accommodation
7212      RV (recreational vehicle) parks and recreational camps
7213      Rooming and boarding houses
81          Other services (except public administration)
811        Repair and maintenance
8111      Automotive repair and maintenance
8114      Personal and household goods repair and maintenance
812        Personal and laundry services
8121      Personal care services
8123      Drycleaning and laundry services
8129      Other personal services
813        Religious, grantmaking, civic, professional, and similar organizations - tax-exempt

pt = industry part

Do seasonally adjusted estimates cover the same time frame as the unadjusted estimates?

Seasonally adjusted estimates are provided for all quarters for which there are unadjusted estimates available. Full time series are accessible here. The quarterly press release contains seasonally adjusted estimates for the most recent six quarters.

Are there plans to expand the number of seasonally adjusted estimates?

Yes. For the full report, we anticipate the introduction of seasonally adjusted estimates of expenses for selected industries within NAICS sectors 62, 71, and 81 effective with the March 2023 release for the fourth quarter of 2022.


  • Selected industries within the following NAICS sectors:
    • 62   Health care and social assistance
    • 71   Arts, entertainment, and recreation
    • 81   Other services (except public administration)

Source: U.S. Census Bureau | Services | (888) 211-5946 |  Last Revised: March 21, 2019 June 16, 2022