adjusted their consumption behavior in ways that are consistent with insulating children from the negative effects of the economic crisis.

Portner (2010) examines the effects of different types of natural shocks–frost, hurricanes, storms, heavy rains, and flooding–on WHZ of Guatemalan children. Estimating the effect of each shock in a separate regression, the author finds a significant, negative effect of frost on WHZ of 0.08 SD, but does not find the same for the other shocks. As Portner notes, the examined shocks occur frequently. Consequently, households may have taken measures to effectively mitigate and cope with these shocks.

_Child weight-for-age z-scores or underweight status_ The collective evidence is strongly consistent that shocks worsen child undernutrition as measured by WAZ or the probability of underweight status. Eight of the 29 reviewed studies provide relevant estimates. These studies provide 10 estimates in total, of which eight are statistically significant in the direction that indicates worsening undernutrition status (see table 4 for a summary of our findings).<sup>4</sup> Among studies that find statistically significant effects, Kumar et al. (2016) find that early-life drought exposure reduces child WAZ by nearly 0.1 SD in India. The authors also find that the probability of being underweight increases by about 1.8 percentage points if the child is exposed to drought in his or her year of birth, and the probability of being severely underweight increases by about 1.5 percentage points. Mendiratta (2015) finds that Indian boys who experience a negative rainfall shock during their first year of life on average observe a reduction in WAZ of 0.22 SD, while Indian girls see a reduction of 0.28 SD. And Ahmed (2015) finds that a decrease in rainfall by 1 SD during the South West monsoon season, which is equivalent to 130 mm of rainfall, reduces child WAZ by 0.63 SD in India.

In terms of statistically insignificant effects, Block et al. (2004) examine the effect of Indonesia’s drought and financial crisis of 1997–98 using time-age-cohort decomposition analyses employing high-frequency nutrition data. They find that child WAZ remained constant throughout the crisis period despite a rapid increase in food prices and reduction in household consumption of rice, eggs, and dark, leafy vegetables. However, the authors note that the absence of effect on child WAZ was the result of an intrahousehold resource reallocation and a coping response that protected child caloric intake at the expense of their food quality. Deuchert and Felfe (2015) exploit variation in Super Typhoon Mike’s effect on housing damage in 1990 in the Philippines to estimate the effect on child WAZ and find that it was insignificant. Children whose housing was not affected were a weak counterfactual as the disaster likely also impacted the local economy, among other things. Moreover, the study notes that households that experienced housing damages were more likely to have received disaster relief, which might have masked the true effect of the shock.

_Child height-for-age z-scores or stunting status_

> 4 Bengtsson (2007), not included in this review, uses rainfall variation as an instrumental variable for income changes and finds that, for children below age 10 in rural Tanzania, a decrease in income by 10 percent increases the probability of being malnourished (defined as child WAZ less than 1 SD below the international reference median) by 7 percent.

7