Level of Travel Time Reliability (LOTTR)
Updated Using 2023 Data

Level of travel time reliability (LOTTR) is a ratio comparing longer travel times (80th percentile) to “normal” travel times (50th percentile). LOTTR assesses the consistency, or dependability, of travel times from day to day or across different times of the day on the State Highway System (SHS).

Methodology

Methodology: Level of Travel Time Reliability (LOTTR)

The level of travel time reliability is calculated for each reporting segment for the following time periods by dividing the 80th percentile travel time by the 50th percentile travel time:

Calculation

AM Peak – 6:00 a.m. – 10:00 a.m. on Monday – Friday

Mid-day – 10:0 0 a.m. – 4:00 p.m. on Monday – Friday

PM Peak – 4:00 p.m. – 8:00 p.m. on Monday – Friday

Weekends – 6:00 a.m. – 8:00 p.m. on Saturday and Sunday


A segment is reliable if its LOTTR is less than 1.5 during all four time periods. If one or more time periods has a LOTTR of 1.5 or above, that segment is unreliable.

Definitions

Definition: Level of Travel Time Reliability (LOTTR)

  • Annual Average Daily Traffic (AADT): The total vehicle volume on a roadway segment over one year, divided by the number of days in the year.
  • Area Type
    • Urbanized Area: An area with a population of at least 50,000 people.
    • Non-Urbanized Area: An area with a population less than 50,000 people.
  • Context Classification: A classification assigned to a roadway that broadly identifies the various built environments in Florida, based on existing or future land use characteristics, development patterns, and the roadway connectivity of an area. For more information about context class, please reference the methodology report.
  • Facility Type
    • Arterials: Signalized roadways that primarily serve through traffic, with intersections spaced two miles or less apart.
    • Highways: High speed roadways with intersections spaced more than two miles apart.
    • Freeways: Multilane, divided highways with at least two lanes for exclusive use of traffic in each direction and full control of ingress and egress.
  • Highway System: An integrated network of roads and highways for motor and non-motor transport. Multiple highway systems exist in Florida. For this specific measure, two highway systems are reported:
    • State Highway System (SHS): Roads under the jurisdiction of the State of Florida and maintained by the Florida Department of Transportation or a regional transportation commission; includes roads with Interstate, US, and SR numbers.
    • Strategic Intermodal System (SIS): A statewide network of high-priority transportation facilities, including the state's largest and most significant airports, spaceports, deepwater seaports, freight rail terminals, passenger rail and intercity bus terminals, rail corridors, waterways, and highways. The FDOT Source Book reports roadway SIS facilities on the SHS or the NHS.
  • Level of Travel Time Reliability (LOTTR): The ratio of the 80th percentile travel time to the 50th percentile travel time.
  • Reporting Periods
    • Peak Hour: 5:00 p.m. to 6:00 p.m. on a weekday. This hour is chosen to allow consistent comparisons among transportation modes. It may not be the hour of greatest travel for any given roadway, mode, or area. The majority of travel typically occurs during the PM peak hour resulting in more congestion in the PM peak than the AM peak.
    • Daily: For the average 24-hour day.
  • Segment: A portion of roadway defined by two boundary points.
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Date of last refresh: 11/22/2024