The level of for-hire freight shipments in September measured by the Freight TSI (139.2) was 1.6% below the all-time high of 141.4 reached in August 2019 (Table 2A). BTS’ TSI records begin in 2000. See historical TSI data.

The August index was revised to 140.3 from 139.9 in last month's release.

BTS will release the passenger and combined indexes for September next month, because air passenger travel continues to deviate from regular seasonal patterns, as it adjusts to the effects induced by the COVID-19 pandemic. The August passenger and combined indexes are available on the BTS website. Air freight and waterborne for September also are statistical estimates. Since air freight and waterborne make up a smaller part of the freight index, the freight TSI is being released as scheduled with the air freight estimate included. 

The Freight TSI measures the month-to-month changes in for-hire freight shipments by mode of transportation in tons and ton-miles, which are combined into one index. The index measures the output of the for-hire freight transportation industry and consists of data from for-hire trucking, rail, inland waterways, pipelines and air freight. The TSI is seasonally-adjusted to remove regular seasonal movement, which enables month-to-month comparisons.

For additional historical data, go to TSI data.

Analysis: The Freight TSI decreased in September due to seasonally adjusted decreases in trucking, pipeline and air freight while rail carload, rail intermodal, and water grew.

The September decrease came in the context of declines in several other indicators. The Federal Reserve Board Industrial Production (IP) Index was down 0.3% in September, reflecting declines of 0.4% in manufacturing and 0.6% in mining while utilities grew by 0.7%. Housing starts were down 0.5% but Personal Income increased by 0.3%.

The Institute for Supply Management Manufacturing (ISM) index was unchanged at 47.2. A reading above 50 indicates an expansion of U.S. manufacturing, while a reading below 50 indicates a contraction.

Although the September Passenger TSI is being withheld because of the previously cited difficulty of estimating airline passenger travel and other components, the August index is now being released. The index increased 0.8% from July to August. Seasonally adjusted transit and rail passenger grew, while air passenger declined.

The Passenger TSI has now exceeded its level in March 2020 —the first month of the pandemic— for thirty-nine months in a row but remains below its pre-pandemic level (February 2020) for the 54th consecutive month.

Trend: The September freight index decrease was the first since June, following two months of growth, leaving the index 0.6% above its level in June 2024. The index increased 4.8% since August 2021. The September Freight TSI exceeds the pandemic low in April 2020 by 12.0%; the index increased month-over-month in 31 of the 53 months since that low. 

For additional historical data, go to TSI data.

Index highs and lows: For-hire freight shipments in September 2024 (139.2) were 46.4% higher than the low in April 2009 during the recession (95.1). The September 2024 level was 1.6% below the historic peak (since 2000) reached in August 2019 (141.4).

Year to date: For-hire freight shipments measured by the index were up 0.5% in September compared to the end of 2023 (Table 3).

Long-term trend: For-hire freight shipments are up 1.0% in the five years from September 2019 and are up 14.0% in the 10 years from September 2014 (Table 5).  

Same month of previous year: September 2024 for-hire freight shipments were up 0.4% from September 2023 (Tables 4, 5). 

3rd quarter changes: The freight TSI fell 1.1% in the 1st quarter, rose 1.0% in the 2nd quarter, and rose 0.6% in the 3rd quarter (Table 6).  

The TSI has three seasonally adjusted indexes that measure changes from the monthly average of the base year of 2000. The three indexes are freight shipments, passenger travel and a combined measure that merges the freight and passenger indexes. See Seasonally-Adjusted Transportation Data for numbers for individual modes. TSI includes data from 2000 to the present. Release of the October 2024 index is scheduled for December 11, 2024.

Revisions: Monthly data has changed from previous releases due to the use of concurrent seasonal analysis, which results in seasonal analysis factors changing as each month’s data are added.    

BTS research has shown a clear relationship between economic cycles and the Freight and Passenger Transportation Services Indexes. See a study of this relationship using smoothed and detrended TSI data. Researchers who wish to compare TSI over time with other economic indicators, can use the FRED database, which includes freight, passenger and combined TSI, and which makes it possible to easily graph TSI alongside the other series in that database. See TSI data on FRED.   

For charts and discussion on the relationship of the TSI to the economy, see Transportation as an Economic Indicator: Transportation Services Index.

A BTS report explaining the TSI, Transportation Services Index and the Economy, is available for download.
 

Table A: Summary of Revisions to Freight TSI in Previous 12 Months

SOURCE: Bureau of Transportation Statistics. See Transportation Services Index for documentation, data and other background information.

NOTE: The entire Freight TSI is revised monthly. Changes shown only for the previous 12 months.

Table 1: Freight Transportation Services Index since March 2024 
Percent Change from Previous Month
(Seasonally Adjusted, Monthly Average of 2000 = 100)

SOURCE: Bureau of Transportation Statistics. See Transportation Services Index for documentation, data and other background information.

NOTE: Percent changes based on numbers prior to rounding.

Table 1A: Annual High and Low Points in Freight Transportation Services Index, 2020-2024 

SOURCE: Bureau of Transportation Statistics. See Transportation Services Index for documentation, data and other background information.

Table 2: Freight Transportation Services Index Monthly Changes, 2021-2024
Percent change from previous month

SOURCE: Bureau of Transportation Statistics. See Transportation Services Index for documentation, data and other background information.

Table 2A: Freight Transportation Services Index by Month, 2021-2024

SOURCE: Bureau of Transportation Statistics. See Transportation Services Index for documentation, data and other background information.

Table 3: Freight Transportation Services Index Year-to-Date Change, 2015-2024
Percent change to September from December of the previous year

SOURCE: Bureau of Transportation Statistics. See Transportation Services Index for documentation, data and other background information.

Table 4: Freight Transportation Services Index from Year-to-Year
Percent Change in the September Freight TSI 
(Monthly average of 2000 = 100)

SOURCE: Bureau of Transportation Statistics. See Transportation Services Index for documentation, data and other background information.

NOTE: Percent changes based on numbers prior to rounding.

Table 5: Freight Transportation Services Index from Previous Years 
Percent Change to 2024 (September to September)

SOURCE: Bureau of Transportation Statistics. See Transportation Services Index for documentation, data and other background information.

Table 6: Freight Transportation Services Index Change by Quarter, 2015-2024
Percent change from the last month of the previous quarter

SOURCE: Bureau of Transportation Statistics. See Transportation Services Index for documentation, data and other background information.

Brief Explanation of the TSI
    
The Transportation Services Index (TSI) is a measure of the month-to-month changes in the output of services provided by the for-hire transportation industries.  The freight index measure changes in freight shipments while the passenger index measures changes in passenger travel. 

The TSI tells us how the output of transportation services has increased or decreased from month to month. The index can be examined together with other economic indicators to produce a better understanding of the current and future course of the economy.   The movement of the index over time can be compared with other economic measures to understand the relationship of changes in transportation output to changes in Gross Domestic Product (GDP).

    
The freight transportation index consists of:
   For-hire trucking,
   Railroad freight services (including rail based intermodal shipments such as containers on flat cars),
   Inland waterways transportation,
   Pipeline transportation (including principally petroleum and petroleum products and natural gas), and
   Air freight.

The index does not include international or coastal waterborne movements, private trucking, courier services, or the US Postal Service.
  
The passenger transportation index consists of:
   Local transit, 
   Intercity passenger rail, and 
   Passenger air transportation. 

The index does not include intercity bus, sightseeing services, ferry services, taxi service, private automobile usage, or bicycling and other non-motorized transportation. 

The TSI includes only domestic "for-hire" freight and passenger transportation. For-hire transportation consists of freight or passenger transport services provided by a firm to external customers for a fee. The TSI does not include taxi services, paid ride services in personal motor vehicles (e.g., Uber, Lyft, etc.), intercity bus services, in-house transportation (vehicles owned and operated by private firms for their own use), or noncommercial passenger travel (e.g., trips in the household car).