is roughly the same size as it was at birth (a start-up size of around 7 employees), an indication that only some firms are growing and doing so substantially.

A number of caveats about the data should be kept in mind. First, the sample of the ES survey, while designed to be nationally representative of the universe of formal private sector firms working in manufacturing and services, is subject to the quality of sampling frames, and information on aggregate figures are subject to issues of nonresponse. The ES relied on several sources to build a sampling frame: the firm registry, the list of firms paying VAT, and the list of large taxpayers maintained by GSS were complemented with additional lists of firms from the Ghana Chamber of Commerce and Industry and Business Associations. Nonetheless, the sampling frame proved to be incomplete and was not sufficient to draw the target sample. A block enumeration was also undertaken in order to build an additional list. The block enumeration allowed a list of establishments to be physically created, from which the sample was drawn.

Based on the ES, the employment stock in 2012 is about 170,000, including permanent and temporary employees, equivalent to about 15 percent of the employment stock estimated in 2012 from Ghana Living Standard Survey round 6 for private workers in the same sectors (about 1.24 million). Considering that not all the private wage workers in those sectors are working in formal firms, and that only about 30 percent of private wage workers report having either a written contract or any type of social insurance benefits (to proxy formal workers), the employment stock captured in the ES formal firms represents about half of the “formal” employment stock estimated through the GLSS6 in the same sectors (World bank 2016). The representativeness of the ES will be further validated once the Establishment census data recently collected by the Ghana Statistical Service will be available.

Two broad metrics of private sector employment are informative.<sup>12</sup> The first is the static stock of employment, which is an indicator of distribution of jobs in the formal private sector. That is, what is the share of private sector employment accounted for by certain types of firms? A second broad metric is the rate of job growth (overall). That is, what is the rate at which the stock of jobs is growing, and which types of firms are responsible for that job growth? The latter metric can be decomposed as well into firms that increased their employment levels between 2010 and 2012 (job growth) and firms that shed jobs (job contractors).<sup>13</sup>

> 12 For a full discussion of results and metrics using similar data, see Aga et al. (2015).

> 13 A well-documented issue with periodic growth data on firm growth and employment is a so-called “reversion-tomean” effect, where growth measures of firms are upwardly biased when the base of the growth rate is the first period considered, as in a common arithmetic growth rate. The source of this bias is that firms that have shed jobs are then the likeliest to quickly add those jobs in times of recovery; conversely, using the end-point of measurement (in this case 2012), has an equivalently downward bias. To ameliorate this problem, the two-period average of full-time employment is used to classify firms, ��,��� � 0.5 ���,���� + ��,����), where _E_ is the full-time employment of firm _i_ in fiscal year 2010 and 2012 respectively (As all figures are based on survey estimates, employment figures are considered as survey-weighted).

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