firms. Taking out these firms from the analysis substantially weakens the association. Nevertheless, if the analysis is restricted to surviving firms (i.e., firms that remained in business during the period studied), there is a clear negative association between _net job creation rates_ and firm age, indicating younger firms create new jobs at a faster rate. In Norway, Klette and Mathiassen (1996) report that gross job creation and destruction rates decline with firm age for manufacturing sector firms. In particular, they show that the _gross job creation rates_ fall off more quickly than _job destruction rates_ as firms mature: consequently, the _net job creation rate_ declines with firm age. Lawless (2014) likewise reports a negative relationship between firm age and _net job growth rates_ . She shows that _gross job creation rates_ decline with firm age while no systematic relation is observed between age and _job destruction rate_ s. Consequently, _net job growth rates_ decline with firm age. Criscuolo et al (2014) furthermore indicate that young firms, 5 or less years old, have higher _net job growth rates_ . Although young and older firms have roughly comparable _job destruction rates_ , younger firms have higher _gross job creation rates_ than their older counterparts; hence the higher _net job growth rates among younger firms_ .

For developing countries, Ayyagari et al (2014) also find that younger firms, 5 years or less, grow faster than older ones. Regarding the contribution to _gross job creation_ , however, the pattern is not clear: younger firms are the largest contributors to gross job creation among small firms (fewer than 20 employees), while older firms are the largest contributors to gross job creation for medium and larger firms.<sup>24</sup> Ma et al (2015) report results using census data for Chinese manufacturing firms over 1998 to 2007, showing that _gross job creation rates_ steeply decline with firm age while _job destruction rates_ increase. Consequently, _net job growth rates_ and firm size are negatively correlated. Eslava and Haltiwanger’s (2014) study on Colombia reports results that are consistent with recent findings for the US (Haltiwanger et al 2013). They show that _net job growth rates_ decline with firm age, noting that the high growth performance by young firms is driven largely by a small group of high growing start-up firms. Nevertheless, they report a pattern where surviving firms grow, but job destruction due to firm exit is not systematically related to firm age, indicating less of the “up-or-out” dynamic reported for US firms. Using manufacturing census data from Ethiopia, Bigsten and Gebreeyesus (2007), report a non-linear relationship between firm age and net job growth rates: job growth declines with firm age for firms 9 years or younger, but increases with age for those over 9 years perhaps indicating that the learning-by-doing benefits are realized only in the later stages of a firm’s life cycle.

# **IV. Updated Results Using Data from the Enterprise Surveys**

In this section we provide estimates for 117 developing economies based on data from the World Bank Group’s Enterprise Surveys. As the bulk of the debate around these measures is centered on the role of size

> 24 Results are not reported on contribution to net job creation and job destruction by firm age

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