/education-data-source-ccd

name: education-data-source-ccd
description: >-
  CCD — federal universe of all U.S. public K-12 schools (~100K) and districts (~18K). Enrollment, staffing, finance, directory data (1986-present). Use for public school analysis by grade/race/sex. Public only; excludes private and postsecondary.
metadata:
  audience: any-agent
  domain: data-source
  skill-authored: "2026-02-09"
  skill-last-updated: "2026-02-09"

CCD Data Source Reference

Common Core of Data (CCD) — the federal complete-universe database of all U.S. public K-12 schools and districts (~100,000 schools, ~18,000 districts), collecting enrollment, staffing, finance, and directory data annually (1986-present). Use when analyzing public school enrollment by grade/race/sex, district finances, school staffing, or directory attributes. Public schools and districts only; excludes private schools and postsecondary. Note significant variable encoding and race/ethnicity definition changes over time.

The CCD is the Department of Education's comprehensive, annual, national database of all public elementary and secondary schools and school districts in the United States. It is the only federal dataset that provides a complete universe census (not a sample) of U.S. public K-12 education.

> **CRITICAL: Value Encoding** > > The Education Data Portal uses **integer codes** for categorical variables that > differ from NCES's original string codes. Always verify codes against codebooks. > > | Context | `school_type` | `charter` | `urban_centric_locale` | > |---------|---------------|-----------|------------------------| > | **Portal (integers)** | `1` (Regular) | `0` (No) / `1` (Yes) | `11` (City-Large) | > | NCES original | `1-Regular school` | `Yes` / `No` | `11-City: Large` | > > **Note:** `charter` and `magnet` use `0/1` encoding, NOT `1=Yes / 2=No` as some NCES documentation shows. > > See `./references/variable-definitions.md` for complete encoding tables.

What is CCD?

• **Primary K-12 database**: DOE's authoritative source for public elementary/secondary education statistics
• **Universe survey**: Covers ALL public schools and districts, not a sample
• **Annual collection**: Data submitted by State Education Agencies (SEAs) each year
• **Six major components**: Directory, Membership, Staffing, Finance (state and district), Dropout/Completers
• **Coverage**: ~100,000 public schools and ~18,000 school districts nationwide
• **Historical depth**: Data available from 1986 to present (varies by component)
• **Collector**: National Center for Education Statistics (NCES) via EDFacts
• **Available through**: Education Data Portal mirrors (5 of 6 survey components; see Data Access section for details)

Reference File Structure

| File | Purpose | When to Read | |------|---------|--------------| | `survey-components.md` | Detailed coverage of each CCD survey component | Understanding what data is collected | | `data-collection.md` | How data flows from schools to NCES, timelines, respondent universe | Understanding data provenance and timing | | `variable-definitions.md` | Key variables, coding schemes, special values | Interpreting specific data elements | | `data-quality.md` | Missing data patterns, suppression, state variations | Assessing data reliability | | `historical-changes.md` | Definition changes, code revisions over time | Longitudinal analysis |

Decision Trees

What CCD component do I need?

What information do you need?
├─ School/district names, addresses, contacts → Directory
│   └─ See ./references/survey-components.md#directory
├─ Student enrollment counts → Membership
│   ├─ By grade → Membership (grade disaggregation)
│   ├─ By race/ethnicity → Membership (race disaggregation)
│   ├─ By sex → Membership (sex disaggregation)
│   └─ See ./references/survey-components.md#membership
├─ Staff/teacher counts → Staffing
│   └─ See ./references/survey-components.md#staffing
├─ Revenue and expenditure → Finance
│   ├─ State-level totals → National Public Education Financial Survey
│   ├─ District-level detail → School District Finance Survey (F-33)
│   └─ See ./references/survey-components.md#finance
├─ Graduation/dropout rates → Dropout and Completers
│   └─ See ./references/survey-components.md#dropout-completers
└─ School type, charter status, locale → Directory
    └─ See ./references/survey-components.md#directory

Is this a data quality issue?

Unexpected data values?
├─ Negative numbers (-1, -2, -3, -9) → Missing data codes
│   └─ See ./references/variable-definitions.md#missing-data-codes
├─ Very different from prior year → Check for definition changes
│   └─ See ./references/historical-changes.md
├─ State appears as outlier → Check state-specific reporting
│   └─ See ./references/data-quality.md#state-variations
├─ Large number of zeros → Check suppression rules
│   └─ See ./references/data-quality.md#suppression
└─ Locale codes don't match → Pre/post 2006 locale system change
    └─ See ./references/historical-changes.md#locale-codes

Can I compare across time?

Building a time series?
├─ Race/ethnicity categories → Major change in 2010
│   └─ See ./references/historical-changes.md#race-ethnicity
├─ Locale codes → Completely revised in 2006
│   └─ See ./references/historical-changes.md#locale-codes
├─ School/district IDs → Check for ID changes
│   └─ See ./references/variable-definitions.md#identifiers
├─ Free/reduced lunch → CEP and direct certification changes
│   └─ See ./references/data-quality.md#frpl
└─ Finance data → Definition changes and inflation
    └─ See ./references/historical-changes.md#finance

Quick Reference: CCD Components

| Component | Level | Key Variables | Years | Update Cycle | |-----------|-------|---------------|-------|--------------| | Directory | School, LEA, State | Name, address, type, status, locale, charter | 1986+ | Annual | | Membership | School, LEA, State | Enrollment by grade, race, sex | 1986+ | Annual | | Staffing | School