What pace did the field actually run, lap by lap?

The trimmed field-average lap time across a race, blending fuel burn, tyre degradation, and track rubbering into one reference baseline.

To say a driver was “fast” you need a yardstick: what did the field run on that lap? The field pace curve builds that yardstick. It plots the trimmed field-average lap time as it evolves over race distance, blending fuel-load drop, tyre degradation, and track rubbering-in into a single reference baseline the curve every other decomposition measures against.

What it shows

The chart overlays a smoothed reference, the raw mean, and a caution flag:

• Smoothed curve: a LOWESS-smoothed field pace that suppresses outliers from safety cars, pit entries, and stint boundaries. This is the primary answer to “what did the field actually run this lap?”
• Raw trimmed mean: the 20th–80th percentile lap time across all eligible cars per lap. The ribbon between the two series shows where smoothing diverges from the raw data a wide ribbon means a noisy lap (few cars, spread strategy).
• Low-sample laps: laps with fewer than 4 eligible cars (pit windows, early laps) are flagged and should be read with caution.

The fuel-corrected rate of change of this curve feeds the base_track_pace_s input to the seven-term decomposition so this is not just a chart, it is an upstream model input.

How to use it

1. Select a race from the filter bar; the curve loads.
2. Read the smoothed curve as the field reference for that race.
3. Watch the ribbon width where the smoothed and raw series diverge, the lap is noisy and the average is less reliable.
4. Discount flagged low-sample laps pit windows and opening laps have too few cars to average well.

Reading the signal correctly

The curve is a trimmed central tendency, not the leader’s pace or the fastest lap it deliberately discards the top and bottom 20% to resist outliers. Its shape combines several physical effects (fuel, tyres, track), so a downward slope is fuel burn and rubbering, not the field simply getting faster.

Early laps and pit windows are sparse and flagged for a reason the curve there leans on a handful of cars and can swing. Don’t read fine structure in the flagged regions.

Data source

The chart queries int_field_pace_curve via DuckDB-Wasm in the browser, for a single race.

Column	Meaning
smoothed_field_pace_s	LOWESS-smoothed field reference pace
trimmed_mean_pace_s	20th–80th percentile lap-time mean per lap
eligible_car_count	Cars contributing to the lap; gates the low-sample flag at < 4

This is a single-race view across 2018–2024 data.

For the full model definition, see the int_field_pace_curve reference.