_L. Fox and A.M. Oviedo_ _Are Skills Rewarded in Sub-Saharan Africa?_

# **II. Data**

We use surveys of manufacturing firms carried out by the world-wide Enterprise Survey project of the World Bank group between 2003 and 2007.<sup>10</sup> The firms surveyed are for the most part registered for tax purposes; they employ at least 5 employees.<sup>11</sup> The manager/owner of the firm is interviewed in detail about basic firm characteristics (age, legal status, etc.), as well as specific investment climate questions, for instance whether the firm has experienced power outages, what the delays have been when it requested a public service, how difficult it is to deal with public officers, etc. In addition, the manager is asked to rank the investment climate obstacles according to his/her opinion (infrastructure, access to finance, labor regulations, crime, corruption, etc., a total of 15 investment climate aspects). In short, the surveys contain a rich set of questions that can be used to relate firm performance to the investment climate of the country.

Our sample covers 12 civil law countries (Benin, Burkina Faso, Burundi, Cameroon, Cape Verde, Democratic Rep. Congo, Guinea, Madagascar, Mali, Mauritania, Rwanda, and Senegal), all of them Francophone, except Cape Verde; and 8 common law countries (all Anglophone): Botswana, Gambia, Ghana, Kenya, Namibia, Swaziland, Tanzania, and Uganda. Within manufacturing, our sample has firms in the following sectors: food & beverages; chemicals, paints & pharmaceuticals; construction materials; metals; paper & printing; plastics; textiles, garments & leather; wood; and other manufacturing.<sup>12</sup> A number of surveys in Africa include a worker module for a sub-sample of randomly selected firms in manufacturing. A maximum of 10 workers were interviewed in each firm.<sup>13</sup> They were asked about their current and starting occupation, wages, tenure, experience, gender, and other relevant questions for Africa (health, transportation, etc.). In most cases, the sample is not random, since the goal was to interview at least one worker in each job category (manager, professional, skilled production, unskilled production, non-production).<sup>14</sup> We use this information, plus the data in the firm surveys, to analyze employment growth and the determinants of wages in African manufacturing firms. Our total number of observations is roughly

> 10 Comprehensive information about these surveys is available at www.enterprisesurveys.org.

> 11 In some countries, separate surveys have been implemented for micro- and informal firms, but we are not using these data at present.

> 12 Hereafter, we refer to common law countries as “Anglophone” and civil law countries as “Francophone”.

> 13 Most firms have at least 6 workers in their sample.

> 14 In the surveys conducted in the last 3 years, worker sampling is done as follows. In a random sample of manufacturing firms, only after the manager agrees, (a) if a list of workers exists, the interviewer(s) obtains the list of workers and randomly selects the predetermined number of employees; (b) if the list does not exists - that is, in most of the cases- the interviewer(s) walks in the factory and randomly selects workers in all categories (professional, skilled, unskilled, manager, etc.) ensuring that all categories are represented. (Personal communication with Giuseppe Iarossi, who oversees data collection in Africa.)

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