# Codebook

`data/clean/ipeds_panel.csv`: one row per (`unitid`, `year`). Years 2003 through 2023. All money columns are in real 2023 dollars.

## Variables

| Variable | Type | Description |
|---|---|---|
| `unitid` | integer | IPEDS institution ID. |
| `year` | integer | Academic year. |
| `inst_name` | character | Institution name. |
| `state` | character | Two-letter postal abbreviation. |
| `carnegie` | character | Basic Carnegie classification. |
| `sector` | integer | IPEDS sector code. |
| `tuition_fees_real` | numeric | In-state undergraduate sticker tuition + required fees, real dollars. |
| `net_tuition_per_fte_real` | numeric | Gross tuition revenue / FTE, real dollars. |
| `state_local_approp_per_fte_real` | numeric | (State + local appropriations) / FTE, real dollars. |
| `fte_enrollment` | numeric | 12-month FTE enrollment. |

## Sample

Public 4-year Title IV institutions, contiguous 48 states. Institutions whose panel-mean FTE is below 1,000 are excluded. Institutions with `state_local_approp_per_fte_real` above $50,000 are excluded.

## Source

- NCES IPEDS bulk-data downloads (HD, IC_AY, F1A, EFIA): https://nces.ed.gov/ipeds/use-the-data
- BLS CPI-U (CPIAUCSL, annual average) from FRED, used for inflation adjustment.

IPEDS data is in the public domain.