Subway Wait Assessment

Issued Date
April 06, 2016
Agency/Authority
Metropolitan Transportation Authority - New York City Transit

Purpose

To determine whether New York City Transit (Transit) provides passengers service on all of its lines that meets its minimum service frequency standards; whether those standards take into account demand for service, physical structure, and other factors; and where Transit fails to meet the wait assessment, whether it determines the causes and takes corrective action to address them. The audit primarily covers the period March 1, 2013 through February 6, 2015.

Background

Transit is a constituent agency of the Metropolitan Transportation Authority (MTA). It serves an average 5.5 million weekday passengers on its 23 subway lines (which includes three shuttle lines). From the original 28 stations built in Manhattan and opened on October 27, 1904, the subway system has grown to 469 stations, most of which were built by 1940.

Wait assessment is a statistic that measures the ability of Transit to provide evenly spaced subway service in conformance with the headways (time between trains) in the official schedule. The assessment determines the number of intervals between trains that meet the standard (headway plus 25 percent) and those that do not. In terms of its stance on the importance of this statistic, Transit has given it a 60 percent weighting of the three components that make up the Service-Key Performance Indicator.

The System Data & Research Division of Operations Planning at Transit calculates the wait assessment statistic based on computerized train tracking information for the numbered subway lines (except the 7 line) and from random sample observations for the remaining lines. This unit generates reports that are used within the Operations Planning (OP) unit. The reports are also reviewed on a monthly basis at the MTA Transit & Bus Committee Meetings. The Rail Control Center (RCC) of the Department of Subways maintains the evenness of service and compliance with the schedule.

Key Findings

  • The MTA has stated that “wait assessment” is the best way to measure customer experience with respect to service reliability. However, wait assessment performance did not improve during our audit period. The goal for meeting the weekday wait assessment standard was 79.4 percent for 2013 and 80.7 percent for 2014 and 2015, with the actual results of 80.3 percent for 2013 and 78.8 percent for 2014. As of June 2015, the year-to-date assessment performance was 78.4 percent or 2.3 percent below the standard.
  • Wait assessment was calculated as a simple mathematical average: the wait assessment percentages for each line were added and the sum divided by the number of lines. This approach lets smaller lines that operate less frequently or shuttle services that provide limited service to carry the same weight in the overall average as a line that runs more frequently over a longer distance. For example, the E train with 199 trains and wait assessment of 74.5 percent and the C train with 108 trains per weekday and a wait assessment of 81 percent carry equal weight in the overall system-wide average. This likely resulted in higher system-wide averages for wait assessment, as lines with lower frequency and shuttles tend to have better wait assessment rates than lines that run more frequently. Further, the public is not made aware of this.
  • Transit addresses on a day-to-day basis the immediate causes for not meeting wait assessment goals. However, Transit has not developed a full and comprehensive plan to deal with the long-term causes of service disruptions, including matters related to major structural and technology improvements.

Key Recommendations

  • Formally assess and revise as necessary the methodologies used to calculate and report wait time performance data. Appropriately weight the performance statistics of the various lines and shuttles and promote full and transparent disclosure of such data.
  • Develop a comprehensive and detailed long-term plan to address the reasons wait assessment performance has decreased. Such a plan should include the structural and information technology improvements that are needed, as well as timeframes and cost estimates to make the required improvements.

Other Related Audit/Report of Interest

Metropolitan Transportation Authority – New York City Transit: Train On-Time Performance (2014-S-56)

Carmen Maldonado

State Government Accountability Contact Information:
Audit Director: Carmen Maldonado
Phone: (212) 417-5200; Email: [email protected]
Address: Office of the State Comptroller; Division of State Government Accountability; 110 State Street, 11th Floor; Albany, NY 12236