are included (so we exclude provisions covering labor and capital flows). This definition is more in line with the spirit of the model that highlights the role of sales and market size in development. Nevertheless, our preferred measure is the one covering all provisions related, directly or indirectly, to trade, as typically, provisions in trade agreements are negotiated jointly. The results in column 4 are almost identical to those in column 1.

In column 5, we rerun the estimation on a select subsample of the data, in order to test whether our results are affected by the additional volatility introduced from the use of income surveys to measure poverty. Specification 5 includes only consumption surveys, reducing the sample to 238 observations. The results are similar as in specification 1, but the standard errors are higher.

In column 6, we consider alternative five-year windows over which the evolution of poverty is examined, in order to explore the sensitivity of our results to the windows selected. When calculating sustained poverty reduction instead of the windows 1981-85, 1986-90, etc. we shift the window one year back to be 1980-84, 1985-89, etc. Right hand side variables are again matched on the first year of the window. Most coefficients in this specification are qualitatively similar to the results in column 1, with the exception of the one on agricultural productivity growth, which now becomes positive, though it remains insignificant. The market size threshold also increases. Based on these results, we conclude that our qualitative results, suggesting large thresholds market size thresholds and an important role of market size for development, are robust to the windows selected, but the exact magnitude of the effects may be affected by the choice of the window.

In the Appendix we report additional robustness checks. Column 1 in Table A1 repeats the results of our baseline specification (column 1 in Table 4) to facilitate comparisons. Column 2 of Table A1 reports results of a specification that includes only geographic and institutional controls. We include variables that the literature has shown to be highly correlated with economic development: the share of land in a tropical climate, the share of land in a desert climate, distance to coast, ruggedness, British legal origins, and French legal origins (the omitted category is socialist legal origins).<sup>13</sup> These variables have high explanatory power as expected: the simple Probit that includes all these variables has a slightly better fit than our baseline specification (AUC: 0.697 relative to an AUC of 0.678 in our baseline model). However, from a policy point of view, this specification is not particularly useful as these geographic and institutional controls cannot be targeted by policy. The fact that our demand-side-framework inspired specification does almost as well as this specification in terms of fit is reassuring.

> 13The data for the share of land in tropical climate, the share of land in desert climate, average distance to ice-free coast and terrain ruggedness are from Nunn and Puga (2012). For origins of legal system (i.e., English, French or socialist) we use data from La Porta et al. (1999).

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