# Domestic Route Passengers – Extraction Methodology

**Extraction date:** 2026-06-18

## Output file
`datasets/transport_aviation/derived/domestic_route_passengers.csv` (102 rows)

## Sources processed
1. `NCAA_2022_annual_executive_summary.pptx` — NCAA 2022 full-year domestic airline aggregates and airline totals.
2. `NCAA_Q1_2023_executive_summary.pptx` — NCAA Q1 2023 domestic airline aggregates and airline totals.
3. `THISDAY_2023_domestic_airline_passengers.md` — 2023 domestic airline passenger totals by airline.
4. `BASL_MMA2_busiest_routes_2026.md` — MMA2 busiest route ranking and aggregate footfall numbers.
5. `BusinessDay_lucrative_routes_plane_shortage_2024.md` — high-frequency route mentions and fleet totals.
6. `TBI_domestic_aircraft_grounded_fleet_types_2024.md` — fleet snapshots by airline, aircraft types, and route fares.

## Methodology
* All PPTX tables were read with `python-pptx`. Slide number and table index are recorded in `page_or_slide_or_article`.
* Markdown articles were parsed with regular expressions; the exact article source URL and date are preserved.
* City pairs were normalised to uppercase three-letter IATA codes separated by a hyphen (e.g. `LOS-ABV`) using a Nigeria domestic-city lookup table.
* Numeric values were stripped of commas and spaces before storage.
* PPTX airline-level totals were restricted to tables that contain known domestic Nigerian carriers; monthly breakdown tables were skipped to avoid duplicate totals.
* Rows that represent aggregates (national or airline-level) have an empty `route` field because the source does not provide route-disaggregated data.

## Row composition
* Total rows: 102
* Rows with a route pair: 10
* Passenger-unit rows (aggregate + airline): 77
* Fleet-unit rows (`aircraft_count`): 18
* Fare rows (`fare_ngn`): 3
* Route ranking rows (`ranking`): 3

## Key limitations
* **No route-level passenger volumes** were found in any source. NCAA summaries and THISDAY provide airline-level or national totals only.
* MMA2 and BusinessDay name high-frequency routes but do not quote per-route passenger numbers.
* TBI provides per-route airfares, not passenger counts, so those rows use `unit=fare_ngn`.
* Fleet snapshots are qualitative or point-in-time counts; some aircraft counts may be approximate (e.g. 'about 6').

## Failures / extraction notes
* None.