half of the table lists the 25 WTO member countries (“Group A”) that will serve as the main sample for the regression analysis that I describe in the next section; these are countries that have bound fewer than one third of their non-agricultural import products. Cameroon has committed to a legally binding upper limit on the smallest share of imported products at 1.7 percent, followed by Tanzania and Gambia.

An examination of the 25 WTO members with less than 33 percent of bound non-agricultural products suggests a number of common characteristics. First, they are disproportionately poor, as only one (Macao SAR, China) has GNI per capita in 2013 greater than the world average of $10,683. Second, with only a handful of exceptions (Bangladesh, Macao SAR (China), Cuba, Sri Lanka, Suriname), Figure 1 reveals that the vast majority of unbound tariffs are geographically located in Sub-Saharan Africa. Third, while there is also a range of large and small (by population) countries with substantial unbound tariffs, in total the numbers add up: more than 700 million people - or 10% of the world’s population - live in WTO member countries that have bound fewer than one third of their non-agricultural tariffs at any level. Finally, the last column on the left half of Table 5 does suggest relatively little variation in average applied tariffs across these countries - with the exception of Macao SAR, China and Mauritius, the average applied MFN tariff (over all products) for the other 23 WTO member countries ranges between 10 and 20 percent. A major element of this is due to the fact that many of these countries are part of the ECOWAS (Economic Community of West African States), which has been developing a customs union arrangement and thus a common external tariff against non-participants, including the MFN tariff that each would apply against imports arising from all other (non-participant) WTO members.

The right side of Table 5 provides similar summary statistics for WTO member countries that have bound between 33 percent and 95 percent of their non-agricultural product tariff lines. These 14 countries (“Group B”) will be used in robustness checks in the formal regression analysis in the next section, but a cursory examination of their economic characteristics suggests that they are much more diverse. At the extremes, some countries on the list are very poor (Central African Republic) and others very rich (Singapore), and with populations that are very small (Brunei and Iceland) or very large (India). The 2013 average applied MFN tariff also ranges substantially from free trade (Hong Kong SAR, China) to 18 percent (Central African Republic). Finally, a country like Turkey in particular is also notable in that - while it may have bound relatively few (only 35 percent) of its non-agricultural products legally at the WTO, it has constrained its applied MFN tariffs through other trade agreement means, i.e., by forming a customs union arrangement with the European Union covering most of its non-agricultural products, with the exception of steel and textiles.

Before moving on, the last note that I make about Table 5 concerns those countries that are _not_ found in the table. I.e., the rest of the WTO membership (more than 100 WTO members) that are not listed in the table have bound 95 percent or more of their non-agricultural products. I have already illustrated the tariff data for some of these countries - i.e., the recently acceded WTO members - in Table 3.

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