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 Find the latest Coronavirus-related transportation statistics on the BTS COVID-19 landing page.

United States Department of Transportation United States Department of Transportation

August 2021 Freight Transportation Services Index (TSI)

Thursday, October 14, 2021

BTS 61-21
Contact: Todd Solomon
Tel:  202-366-0573
todd.solomon@dot.gov

 

 

The Freight Transportation Services Index (TSI), which is based on the amount of freight carried by the for-hire transportation industry, fell 0.4% in August from July according to the U.S. Department of Transportation’s Bureau of Transportation Statistics (BTS). From August 2020 to August 2021, the index rose 1.4 percent compared to a decline of 6.8 percent from August 2019 to August 2020 and a rise of 3.9 percent from August 2018 to August 2019 (Tables 1, 2, and 2A). The index has declined for the past four months, which is consistent with the modal trends during the summer as discussed in the Analysis section below.

 

The level of for-hire freight shipments in August measured by the Freight TSI (134.1) was 5.6% below the all-time high level of 142.0 in August 2019 (Table 2A). The August 2021 level was 7.9% above the COVID-19 low reached in April 2020. BTS historical TSI records begin in 2000.

Monthly numbers for May and June 2021 were revised down slightly.

BTS is delaying the scheduled release of the passenger and combined indexes for August. The passenger index for August is a statistical estimate of airline passenger travel and other components based on historical trends up to July 2021. The statistical estimate does not fully account for the rapidly changing impacts of the coronavirus on the historical trend. Air freight for August is also a statistical estimate. Since air freight makes up a smaller part of the freight index, the freight TSI is being released as scheduled with the air freight estimate included. The July passenger and combined indexes are available on the BTS website.

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.

Analysis: The Freight TSI decreased 0.4% in August from July due to seasonally-adjusted decreases in rail carloads, rail intermodal, airfreight, and water, while pipeline increased and trucking was stable. The August decrease took place against a background of growth for other indicators.

The Federal Reserve Board Industrial Production (IP) Index grew 0.4% in August, reflecting increases of 0.2% in manufacturing and 3.3% in utilities, while mining shrank by 0.6%. Housing starts were up 3.9% Personal Income increased by 0.2%. The Institute for Supply Management Manufacturing (ISM) index was up 0.4 points to 59.9, indicating accelerating  growth in manufacturing.

Although the August Passenger TSI is being withheld because of the previously cited difficulty of estimating airline passenger travel and other components, the July index is now being released. The index increased 7.4% from June to July following an increase of 8.2% in June. Air passenger, rail passenger and transit all grew. The Passenger TSI has now exceeded its level of March 2020, the last month before the full impact of the pandemic, for two months in a row, though it has not returned to its level in February 2020. It remained below any level the Passenger TSI had been before the pandemic for the 17th consecutive month. 

Trend: The August freight index decrease was the fourth consecutive decrease for a decrease of 2.5% since April. This was the fifth decrease in seven months. The Freight TSI is at its second lowest level since November 2020 but is 7.0% above the pandemic low in April 2020. The index is 5.6% below its record level of 142.0 in August 2019 and has decreased in thirteen of the last 24 months since that peak. For additional historical data, go to TSI data.

Index highs and lows: For-hire freight shipments in August 2021 (134.1) were 41.3% higher than the low in April 2009 during the recession (94.9). The August 2021 level was 5.6% below the historic peak reached in August 2019 (142.0) (Table 1A).

Year to date: For-hire freight shipments measured by the index were down 0.6% in August compared to the end of 2020 (Table 3).

Long-term trend: For-hire freight shipments are up 8.2% in the five years from August 2016 and are up 20.9% in the 10 years from August 2011 (Table 5). 

Same month of previous year: August 2021 for-hire freight shipments were up 1.4% from August 2020 (Tables 4, 5).

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 September 2021 index is scheduled for November 10, 2021.

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 1: Freight Transportation Services Index since February 2021
Percent Change from Previous Month
(Seasonally-Adjusted, Monthly Average of 2000 = 100)

 

Freight

Index

Pct. Change 

February

133.4

-2.4

March

135.9

1.9

April

137.6

1.3

May

137.1

-0.4

June

136.6

-0.4

July

134.6

-1.5

August

134.1

-0.4

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, 2009-2021

Year

 

Month

Peak

Month

Bottom

2009

December

101.9

April

94.9

2017

December

133.6

January

124.0

2018

November

139.6

January

131.6

2019

August

142.0

August

136.7

2020

May

136.6

April

125.3

2021

(thru August)

April

137.6

October

133.4

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

 

Table 2: Freight Transportation Services Index Monthly Changes, 2018-2021
Percent change from previous month

 

2018

2019

2020

2021

 

% Change

% Change

% Change

% Change

January

-1.5

0.8

-0.1

1.3

February

1.9

-0.6

-0.2

-2.4

March

1.1

0.1

-0.9

1.9

April

0.0

0.8

-7.3

1.3

May

0.7

0.4

1.6

-0.4

June

0.6

-0.4

1.6

-0.4

July

-0.9

0.6

3.4

-1.5

August

0.4

1.4

-1.1

-0.4

September

1.2

-2.6

0.2

 

October

0.6

0.0

0.7

 

November

0.3

0.0

-0.3

 

December

-1.4

-1.2

1.4

 

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

 

Table 2A: Freight Transportation Services Index by Month, 2018-2021

 

2018

2019

2020

2021

January

131.6

138.7

136.6

136.7

February

134.1

137.9

136.3

133.4

March

135.6

138.1

135.1

135.9

April

135.6

139.2

125.3

137.6

May

136.6

139.8

127.3

137.1

June

137.4

139.3

129.4

136.6

July

136.2

140.1

133.8

134.6

August

136.7

142.0

132.3

134.1

September

138.4

138.3

132.5

 

October

139.2

138.3

133.4

 

November

139.6

138.3

133.0

 

December

137.6

136.7

134.9

 

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, 2012-2021
Percent change to August from December of the previous year

Year

Freight

2012

-1.9

2013

3.9

2014

2.5

2015

0.2

2016

2.7

2017

3.7

2018

2.3

2019

3.2

2020

-3.2

2021

-0.6

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 August Freight TSI
(Monthly average of 2000 = 100)

 

August Freight TSI

Percent change from same month previous year

2012

112.9

1.8

2013

116.7

3.4

2014

120.8

3.5

2015

123.4

2.2

2016

123.9

0.4

2017

129.3

4.4

2018

136.7

5.7

2019

142.0

3.9

2020

132.3

-6.8

2021

134.1

1.4

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 2021 (August to August)

Since August        . . .

Duration in years

Freight TSI Percent change to August 2021

2020

1

1.4

2019

2

-5.6

2018

3

-1.9

2017

4

3.7

2016

5

8.2

2015

6

8.7

2014

7

11.0

2013

8

14.9

2012

9

18.8

2011

10

20.9

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).