RWI/ISL-Container Throughput Index

RWI/ISL-Container Throughput Index ending 2017 on a positive note

The Container Throughput Index of the RWI – Leibniz Institute for Economic Research and the ISL – Institute of Shipping Economics and Logistics recorded a strong increase during January 2018, climbing from a value of 131.9 in December 2017 (revised figure) to 134.4 in January 2018. This is one of the highest monthly growth rates observed during the last eleven years. As such, it would seem that world trade continues to grow noticeably. However, because of the rather late Chinese New Year festivities, a clearer picture will present itself with the compilation of the February figures.

As usual, at the start of every year, the index compilation process is updated. This time, six new ports have been added: Alexandria (Egypt), Rio Grade do Sul (Brazil), Cartagena (Columbia), Bandar Abbas (Iran), Piraeus (Greece), and Sines (Portugal). This update is partially responsible for the strong revision (+1.3 points) of the December 2017 figure. On average the values for 2017 are now higher by 1.1 points. After including the aforementioned ports, the seasonally adjusted RWI/ISL-Container-Throughput Index seems to be even more closely correlated to the recent world trade development, although the changes to the long-run time series are effectively quite small.

The index is based on data continuously collected from world container ports by ISL as part of its market monitoring. Because large parts of international merchandise trade are transported by ship, the development of port handling is a good indicator for world trade. As many ports release information about their activities only two weeks after the end of the respective month, the RWI/ISL Container Throughput Index is a reliable early indicator for the development of international merchandise trade and hence for the activity of the global economy. As of 2018, the index is compiled based on data of 88 ports. Together these ports account for ~60% of worldwide container handling. The flash-estimate for January is based on data reported by 44 ports, accounting for three quarters of the total index volume.

The RWI/ISL-Container Throughput Index for February 2018 will be released on 20 March 2018.


Prof. Dr. Roland Döhrn

Phone: +49 201 8149-262

Dr. Sönke Maatsch

Institut für Seeverkehrswirtschaft und Logistik
Tel.: (0421) 22096-32

Background Information

The Container Throughput Index is a joint project of RWI with the Institute of Shipping Economics and Logistics (ISL). It aims at providing timely information on short term trends in international trade. The index is based on the consideration that containers have become the most important means of transporting processed products. Therefore, the global container throughput and international trade can be expected to be highly correlated.

Container Throughput Index

As a part of their monthly reporting many ports publish data on container throughput expressed in twenty foot equivalent units (TEU). ISL collects these data systematically in its port database. The 88 ports covered in the index account for about 6 out of 10 containers handled worldwide.

Calculating the indicator starts about 20 days after the end of each month. At that time, about 25 ports have already published information about the container throughput in the latest months, which allows for a flash estimate of the indicator. Data still missing are forecasted using statistical time series models. Thereafter, the data are added up and the sum is adjusted for seasonal and calendar effects. Furthermore, the trend-cycle component of the seasonally adjusted figures is estimated to eliminate irregular influences. One month later, as a rule data on 65 ports are available. Then an update of the figures already published is made and a new flash estimate for the latest month is released.

Hitherto, the RWI/ISL-Container Throughput Index shows a close correlation with world trade. The index provides valuable input into business cycles analyses, since it is available 3 to 4 months in advance of data on world trade published by international organizations, and one month in advance of the first estimates of world trade volumes.

Related Publications

Articles in other journals


Döhrn, R. (2016), Neuberechnung des RWI-ISL Containerumschlag-Index: Der Einfluss des chinesischen Neujahrsfestes. RWI Konjunkturberichte 67 (4): 49-52. download


Döhrn, R. und S. Maatsch (2012), Der RWI/ISL-Containerumschlag-Index – Ein neuer Frühindikator für den Welthandel. Wirtschaftsdienst 92 (5) download

Döhrn, R. (2012), Containerumschlag-Index als Frühindikator für den Welthandel. Schiff & Hafen 2012 (8): 14–16.