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Appendix A: Methodology and Technical Notes

Common Core of Data survey system. The Common Core of Data (CCD) is the primary National Center for Education Statistics (NCES) database on public elementary and secondary education in the United States. The CCD is an annual comprehensive national statistical database of all public elementary and secondary schools and local education agencies (also referred to as school districts). The CCD contains both nonfiscal and fiscal components. The State Nonfiscal Survey of Public Elementary/Secondary Education, the Local Education Agency Universe Survey, and the Public Elementary/Secondary School Universe Survey are the nonfiscal components, while the School District Finance Survey (F-33) and the National Public Education Financial Survey (NPEFS) are the fiscal components.

State education agencies (SEAs) report data for these CCD surveys annually to NCES. The U.S. Census Bureau conducts the data collection for the finance surveys on behalf of NCES. NCES collects data for all three CCD nonfiscal universe surveys through the EDFacts submission system. The membership data used in this report come from the State Nonfiscal Survey. SEAs participate in CCD voluntarily, following standard definitions for the data items they report.

NPEFS data collection. Each year SEAs enter the NPEFS data online through a web application during the NPEFS collection period. SEAs enter new data for the current fiscal year, but also have the opportunity to make revisions to the prior fiscal year data (these revisions are included in the tables found in appendix C). The NPEFS data are certified by an authorizing official from each SEA no later than 5 business days of submission of data on the NPEFS Web form. NPEFS survey analysts then process, edit, and verify the data before publication. The fiscal year 2013 (FY 13) NPEFS collection opened on January 30, 2014. SEAs were urged to submit accurate and complete data for FY 2013 by March15, 2014. The deadline for the final submission of all data, including any revisions to previously submitted data for FY 2013 and FY 2014, was August 14, 2015. All states, the District of Columbia, and the five U.S. Island Areas reported data in the FY 13 NPEFS collection.

Editing data to ensure data quality. NCES Statistical Standards require that all NCES data be edited to ensure data quality. Data editing is an iterative and interactive process that includes procedures for detecting and correcting errors in the data (NCES 2014). When SEA coordinators enter data into the NPEFS collection system, the system applies a set of automated procedures (sometimes referred to as business rules) to detect potential errors or inconsistencies in the reported data. CCD survey analysts review the data submitted from state coordinators and work with state fiscal coordinators to correct or confirm any numbers that appear out of range when compared with other states' data or with the state's reports in previous years. If an SEA does not provide a correction or reasonable explanation for anomalous data, NCES will edit the data based on a set of defined business rules.

Imputation for missing data. Imputation is a procedure that uses available information and some plausible assumptions to derive substitute values for missing values in a data file (NCES 2014). Imputations modify values for cases or records where data are missing (i.e., not reported or suppressed because they did not meet NCES data quality standards). In the case of missing data, an imputation assigns a value to the missing item using a consistent statistical methodology. As a result, subtotals that include this item are also adjusted. The same imputation methodology is used for both revenues and expenditures. Revenues are imputed based on total revenues in reporting states, and expenditures are imputed based on total expenditures in reporting states. All imputed values in the tables in this report are noted. Imputed values are not used in the imputation of other values. Totals and subtotals in tables are noted if one or more items in the total or subtotal are imputed or edited. In some instances, redistribution of reported values to correct for missing data items may affect state values.

Student membership. Each school year SEAs report student membership counts by grade on the State Nonfiscal Survey of Public Elementary/Secondary Education. The FY 13 NPEFS data file includes total student membership reported on the school year 2012–13 State Nonfiscal Survey that includes grades prekindergarten through grade 12 (plus ungraded). If the reported fiscal data excludes prekindergarten programs, total membership on the NPEFS data file also excludes prekindergarten membership. As part of the FY 13 NPEFS collection process, NCES asked SEAs to review student membership data from the State Nonfiscal Survey and verify that the membership data are consistent with the programs covered in the revenues and expenditures data reported in NPEFS. Wyoming indicated that the state fiscal data reported in NPEFS excluded prekindergarten programs. In this state, the NPEFS total student membership variable excludes prekindergarten membership. Illinois did not include finance data for charter schools in the FY 13 NPEFS survey. NCES edited the NPEFS total student membership variable for Illinois by excluding students from districts where all associated schools are charter schools.

Totals. National totals reported in the tables are limited to the 50 states and the District of Columbia and do not include data from the 5 other jurisdictions of American Samoa, Guam, the Commonwealth of the Northern Mariana Islands, Puerto Rico, or the U.S. Virgin Islands.

Current expenditures. Researchers generally use current expenditures instead of total expenditures when comparing education spending between states or across time because current expenditures exclude expenditures for capital outlay, which tend to have dramatic increases and decreases from year to year. Also, the current expenditures commonly reported are for public elementary and secondary education only. Many school districts also support community services, adult education, private education, and other programs, which are included in total expenditures. These programs and the extent to which they are funded by school districts vary greatly both across and within states.

Comparing the NCES School District Finance Survey (F-33) and NPEFS. NPEFS reports many of the same data items as the School District Finance Survey (F-33), but there are differences between the two collections. The survey coverage is different as NPEFS includes special state-run and federal-run school districts that are not included in the F-33. Expenditures on state-run schools are included on NPEFS, but are excluded on the F-33. The data availability also varies because some data might be available at the state level but not available at the district level, so the state-aggregated district totals from F-33 might not be equal to the state totals in NPEFS. The data may also vary because of different "crosswalk" procedures that are utilized when certain states submitted NPEFS and F-33 data in their own format instead of the NCES-requested format.1 In these instances, Census Bureau analysts have to "crosswalk" the state-formatted data to NCES-format data. Differences in expenditures for similar data items between the two surveys can occur based on the methodology that the Census Bureau uses to "crosswalk" data submitted in the SEA format to F-33 variables, or due to how the state respondents "crosswalk" their NPEFS or F-33 data. For example, in some SEA format states there are going to be differences in how certain codes are cross-walked between surveys. Finally, the imputation and editing processes and procedures between the two surveys can vary. For further detail on imputations and editing data please see Documentation for the NCES Public Education Financial Survey (NPEFS) School Year 2012-13 (Fiscal Year 2013) (NCES 2015-302) and Documentation for the NCES School District Finance Survey (F-33), School Year 2012-13 (Fiscal Year 2013) (NCES 2015-304).

Inflation-adjusted data. When comparing dollar amounts between two or more fiscal years, NCES adjusts the older data for inflation to the most recent fiscal year using the Consumer Price Index (CPI) that has been converted from a calendar year basis to a fiscal year basis (July through June).2 The CPI is published by the U.S. Labor Department, Bureau of Labor Statistics. This price index measures the average change in inflation of a fixed market basket of goods and services purchased by consumers.

Fiscal years. The fiscal year used by most SEAs begins on July 1 and ends on June 30. The fiscal year for Alabama and Washington, DC runs from October 1 through September 30, and the fiscal year for Nebraska, Texas, and Washington runs from September 1 through August 31. NCES does not adjust NPEFS data to conform to a uniform fiscal year across states. A fiscal year relates to school year as the latter year of the school year range. For example, FY 13 corresponds to school year 2012–13.

ARRA data. In February 2009, Congress passed the American Recovery and Reinvestment Act of 2009 (ARRA). The ARRA legislation allocated federal education funds directly to the states.3 As a result of ARRA, NCES added seven data items to NPEFS in order to collect and analyze data pertaining to Title I, Impact Aid, and other ED funds (Office of the Federal Register 2009). NCES collected ARRA-related data in the NPEFS collection for FY 09, FY 10, FY 11, FY 12 and FY 13.

For a more comprehensive explanation of the methodology utilized by NPEFS, please see Documentation for the NCES National Public Education Financial Survey (NPEFS), School Year 2012-13 (Fiscal Year 2013) (NCES 2015-302).

The NPEFS data files can be accessed at

1 The "crosswalk" translates the amounts states report in state agency format to NPEFS and F-33 survey variables.
2 FY 12 data used for comparisons in the selected findings and FY 12 data in tables 2 and 5 were adjusted to FY 13 dollars by multiplying the reported variable by 1.01664139916068. Digest of Education Statistics, Selected 2013 Tables, Table 106.70, downloaded March 11, 2015.
3, retrieved June 14, 2015.