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Statistical Standards
Statistical Standards Program
Table of Contents
1. Development of Concepts and Methods
2. Planning and Design of Surveys
3. Collection of Data
4. Processing and Editing of Data
5. Analysis of Data / Production of Estimates or Projections
6. Establishment of Review Procedures
7. Dissemination of Data
Appendix A
Appendix B
Appendix C

·Sample Table
·Major Types of Tables
·Tabular Format
·Table Titles
·Table Stub
·Tabular Notes
·Sizing a Table
Appendix D
Publication information

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Tabular notes contain supplementary information necessary for a correct understanding of the table or a part of it. They fit into two categories: (1) headnotes at the top of the table are used only occasionally, and (2) footnotes at the bottom of the table are used often. Footnotes include general notes, reference notes, and source notes.

Tabular notes should be kept as brief as possible without sacrificing clarity. Topical style is used, with subject-noun, verb, articles, and other parts of speech omitted if not essential to understanding.

A headnote is a special explanation that should be seen before the rest of the table is read. The headnote should be used only when it applies to all or almost all of the cells in the body of the table or if it clarifies the contents of the table by expanding or qualifying the title. Sometimes, careful wording of title and column heads can eliminate the need for headnotes. Consider, instead of the headnote, a general note (NOTE: Data are . . . . .), or a reference footnote with the symbol attached to column heads or stub. Reference notes attached to the title should be avoided, if possible.

A headnote should be centered above the boxhead; if two lines are needed, the second should be centered under the first. It should be enclosed in brackets and typed in lowercase letters, except for the first letter of the first word and the first letters of proper nouns and adjectives. No period is placed after the last word; if more than one sentence, a period ends all but the last sentence. The following are typical examples of headnotes.

[Based on a 10-percent sample of applications]

[Includes both public and private]

[Millions of dollars]

Sometimes a headnote may indicate a unit of measurement that applies to some, but not all, of the columns of figures:

[Dollar amounts in thousands]

Normally, one blank line separates the headnotes from the table title; but more room may be left, if necessary, to make the table fit the available space. Two blank lines usually separate the headnote from the top line of the boxhead.

Special notes
Special notes are notes that are standard for cells in the body of tables and usually refer to a statistical property of the specific cell (e.g., not applicable, missing, an unstable estimate, statistically significant). Special notes fill cells in the body of tables, and do not require parentheses. When special notes are used, they should always be listed in the following order. The following list summarizes a number of statistical special notes and related set of symbols that should be used consistently across all NCES reports. If necessary additional explanatory notes may be added to the end of relevant notes.

Symbol Label Meaning
Not available Data were not collected or not reported
Not applicable Category does not exist
# Rounds to zero The estimate rounds to zero
! Interpret data with caution Estimates are unstable
Reporting standards not met Did not meet reporting standards
* p<0.05 Significance level

General, reference, and source notes fall at the bottom or "foot" of the table. General notes refer to all or much of the table; reference notes, to specifically designated portions; and source notes identify sources of the data. All end with a period.

General notes
General notes, like the headnotes, qualify, describe, or explain whole tables or easily identifiable parts of them. The choice between a general note and a headnote is guided by the degree of emphasis required, and the length and detail included in the note.

The general note is introduced with the word "NOTE" followed by a colon. For example:

NOTE: Detail may not sum to totals because of rounding.

Reference notes
Reference notes refer to specifically designated portions of the table. By "keying" the note to the material to be qualified reference notes can be kept brief.

Example of classroom teachers: full-time, part-time, and FTE. Note on FTE is 'Full-time equivalent of full-time and part-time'

The positioning of symbols for reference notes in tables follows definite principles. The symbols are placed at the right of the word the note applies to, in both headings and stubs. They are placed at the right of data in the field of a table; and if a numbered footnote stands alone in a cell, it is enclosed in parentheses: (1). Footnotes are numbered sequentially throughout a single table, but a recurrent reference repeats the symbol. Footnotes follow a logical order, generally line for line from left to right and down.

The placement of footnote symbols within a table and the arrangement of notes at the end of the table are illustrated in the following table. Footnotes are placed at the end of the table. Special notes are listed first, followed by reference footnotes, general notes, and then the source.

Table 1.  Families, by family status and presence of own children
                under 18: Current Population Survey, 1970 to 1998

Example of table notes: Special symbols are listed first. Numerical footnotes follow. NOTE: the general note comes next. SOURCE: the source comes last.

Source notes
The source note indicates the specific source of the statistic. In general, the source note refers the user to the original (or primary) source and gives credit to the originating report, or in the case of new tabulations, the data file.

The source note should cite the report, relevant survey(s) or sub-survey(s), data reference year, file version number, department name, and agency name. In the case of unpublished data, use the month and year of the tabulation or data file. If the data are drawn from multiple years: for one to three years, report each year; for more than three continuous years, use the year span; and for more than three noncontinuous years use "selected years" and the year span.

Following are some typical examples:

Data from one or more reports:

Revenues and Expenditures for National Public Elementary and Secondary Education: School Year 1997-98, Common Core of Data (CCD), "National Public Education Financial Survey" (NPEFS), 1997-98, Version 1, U.S. Department of Education, National Center for Education Statistics.

Data from unpublished tabulations and a published NCES report:

SOURCE: U.S. Department of Commerce, Bureau of the Census, Current Population Survey, Previously unpublished tabulation (April 1998); and U.S. Department of Education, National Center for Education Statistics, Dropout Rates in the United States. Selected years 1972-97.