 If you care about the eradication of poverty, sustainable growth, the one thing that we really need is data. It will help policymakers to assess whether the policies that they have in place at the moment are working. As you and you wider, we've put together the government revenue data set. We looked at the relationship between changes in the tax structure and economic growth rates. And we found that existing beliefs which were based on studies that only considered a richer subset of countries don't hold whenever we are able to employ new data which included more low income, more developing countries. In fact, we find considerable differences in the results across income groups. A key lesson for tax research is that you cannot take tax data from different sources alongside each other at face value. The user needs to understand how they, for example, treat earnings from natural resources or social security contributions. It differs from source to source. In Vietnam, WIDER has collaborated with a number of domestic and international institutions to design and implement the Vietnam Access to Resources Household Survey. In order to get this data, we had to build good working, trusting relationships with the local government and also get the central government to use that data. So the big lesson from the efforts that we have made is that you need long lasting, committed relationships with the local government at all levels.