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Non-tariff and overall protection: evidence across countries and over time

Niu, Zhaohui; Liu, Chang; Gunessee, Saileshsingh; Milner, Chris


Zhaohui Niu

Chang Liu

Saileshsingh Gunessee

Chris Milner


This paper analyzes the evolution of the incidence and intensity of non-tariff measures (NTMs). It extends earlier work by measuring protection from NTMs over time from a newly available database and provides evidence on the evolution of NTMs. In particular, building on Kee, Nicita and Olarreaga (2009), this paper estimates the ad valorem equivalents (AVEs) of NTMs for 97 countries at the product level over the period 1997 to 2015. We show that the incidence and the intensity of NTMs were both increasing over this period, with NTMs becoming an even more dominant source of trade protection. We are also able to investigate the evolution of overall protection derived jointly fromtariffs and NTMs. The results show that the overall protection level, for most countries and products, has not decreased despite the fall in tariffs associated with multilateral, regional and bilateral trade agreements in recent decades. We also document an increase in overall trade protection during the recent 2008 financial crisis. Overall, this study sheds light on an under-researched aspect of trade liberalization: the proliferation and increase of NTMs.


Niu, Z., Liu, C., Gunessee, S., & Milner, C. (2018). Non-tariff and overall protection: evidence across countries and over time. Review of World Economics, 154(4), 675–703.

Journal Article Type Article
Acceptance Date Mar 28, 2018
Online Publication Date May 9, 2018
Publication Date 2018-11
Deposit Date Apr 11, 2018
Publicly Available Date May 9, 2018
Journal Review of World Economics
Print ISSN 1610-2878
Electronic ISSN 1610-2886
Publisher Springer Verlag
Peer Reviewed Peer Reviewed
Volume 154
Issue 4
Pages 675–703
Keywords Non-tariff barriers, tariff equivalents, protection
Public URL
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