OnTimeStats

Historical on-time performance

Decatur to Chicago

156 miData through May 2026Source: US DOT · BTS

Flights on DEC–ORD arrive on time 65% of the time over the last 12 months.

On-time rate65%arrived within 15 min
p90 delay80 min1 in 10 flights is worse (tail risk)
Cancelled4.8%of scheduled flights

based on 627 flights over the last 12 months. On-time means arriving within 15 minutes (BTS standard).

By airline

How each carrier compares

  • SkyWest Airlines
    On-time65%
    Medianon time
    p9080 min
    Cancel4.8%
    Flights627

Why flights run late

Delay causes

  • Airline40%
  • Weather8%
  • Air traffic (NAS)13%
  • Late aircraft39%
  • Security0%

Most delay minutes here are attributed to Airline.

When flights don't go

Why flights were cancelled

  • Airline0%
  • Weather87%
  • Air traffic (NAS)13%
  • Security0%

Most cancellations here are attributed to Weather. Shares are among 30 cancellations with a reported cause (BTS reports causes from June 2003).

Over time

On-time trend

By season

On-time rate by month

When to fly

Best time to fly DEC → ORD

All airlines · rolling 36 months (2023-06 .. 2026-05).

Best time of day

On-time rates are fairly even by time of day on this route — ranging from 57% to 80% on time.

  • Mornings80% on time · p90 80 min · 729 flights
  • Afternoons79% on time · p90 60 min · 414 flights
  • Middays77% on time · p90 80 min · 242 flights
  • Evenings57% on time · p90 90 min · 493 flights

Best day of week

On-time rates are fairly even by day on this route — ranging from 69% to 77% on time.

  • Mondays77% on time · p90 65 min · 310 flights
  • Wednesdays76% on time · p90 90 min · 310 flights
  • Tuesdays74% on time · p90 85 min · 160 flights · limited
  • Fridays73% on time · p90 75 min · 314 flights
  • Saturdays72% on time · p90 75 min · 162 flights · limited
  • Thursdays72% on time · p90 70 min · 309 flights
  • Sundays69% on time · p90 105 min · 313 flights

Keep exploring

Related pages

Methodology

A flight is on time when it arrives within 15 minutes of schedule — the US DOT / BTS standard. Median and p90(the “1-in-10 bad day”) are read from the full arrival-delay distribution, never averaged across periods.

Figures cover a carrier’s own BTS-coded flights. Cells below ~200 flights are flagged as limited data. All numbers are pre-computed from public BTS On-Time Performance data.