Reliability
On-time share and bus spacing by route, stop and hour of day.
“Which hours have the most late arrivals on route 15?”
From RTD GTFS schedules and GTFS-Realtime
Ask how Denver’s buses are really running.
Ask about Denver-area bus and rail service in plain English. WhyLine writes the SQL, shows it to you before it runs, and gives you a table, chart or map to download. Free and open source.
What you can ask about
Each topic is a line on the map. Ask within one, or ask a question that rides across several.
Weather
How on-time performance shifts on days with rain or snow.
“Do snowy days lower on-time performance on route 0?”
From NOAA daily observations at Denver International Airport
Safety
Reported traffic crashes within 250 meters of each stop.
“Which stops have the most crashes nearby?”
From Denver Open Data crash records
Equity and access
Where weak service overlaps with neighborhoods that rely on transit, and how much sidewalk is near each stop.
“Which high-need stops have the least sidewalk around them?”
From U.S. Census ACS 2023 and Denver’s sidewalk inventory
How it works
Nothing runs until you’ve seen the query.
Ask
Type a question, or pick a ready-made one. Date, route and stop filters narrow it down.
Check the SQL
WhyLine writes the query and shows it to you. Edit it if you like. Only read-only queries on approved tables can run.
Explore and download
See the result as a table, chart or map. Download it as CSV, or download a whole table.
SELECT route_id, AVG(pct_on_time) AS avg_pct_on_time
FROM mart_reliability_by_route_day
WHERE service_date_mst >= DATE_SUB(CURRENT_DATE, INTERVAL 30 DAY)
GROUP BY route_id
ORDER BY avg_pct_on_time ASC
LIMIT 10What the numbers mean
Read these before you quote a result.
Sampled, not complete
Reliability comes from sampled realtime observations, not every scheduled arrival. Treat on-time shares as estimates.
A day behind
Realtime data is collected through the day, but the dashboard reads a nightly snapshot. It’s not a live arrivals board.
Context, not cause
Crashes near a stop don’t mean transit caused them. Census figures describe areas, not individual riders.
Independent
WhyLine Denver is not an official RTD or City of Denver service. Read the metric definitions
Where the data comes from
Public sources, collected on a schedule and joined in one warehouse.
- RTD GTFS schedulesRoutes, stops, trips and timetables.
- RTD GTFS-RealtimeTrip updates and vehicle positions, sampled through the day.
- Denver Open DataReported traffic crashes and the city’s sidewalk inventory.
- NOAA daily weatherPrecipitation, snow and temperature at Denver International Airport.
- U.S. Census ACS2023 five-year estimates for Denver County census tracts.
Questions
Do I need an account?
No. Open the dashboard and start asking.
Is this official RTD data?
It’s built from RTD’s public feeds, but WhyLine Denver is an independent project, not an RTD service.
Can I plan a trip or see live arrivals?
No. WhyLine is for looking at how service has performed. It has no trip planner, live arrivals, passenger counts, fares, crowding or service alerts.
What happens to my question?
It’s sent to Google’s Gemini service to write the SQL. Our logs keep only a one-way hash of it, not the text, and your browser remembers your last question and query until you clear them. The privacy policy has the details.
Can I use the data elsewhere?
Yes. Download any result, or a whole table, as CSV. The code is MIT-licensed on GitHub. Check each source’s terms before redistributing its data.