16). Moreover, there are many instances in which the EM-DAT records no disaster impacts at all. This is true especially for droughts, where the microdata suggests that droughts are prevalent to some degree across every country-year combination covered, while EM-DAT records droughts affecting the population in only a third of cases. Estimates of the economic value of disaster impacts are mostly missing in the EMDAT data for the study countries, even in years when drought and flood events were recorded to affect the population in the study countries (Tables 15 and 17).

Large, salient drought and flood episodes have better coverage in the EM-DAT, such as the severe droughts in Niger in 2011<sup>31,32</sup> and Ethiopia in 2015-16,<sup>33,34</sup> or the droughts and floods Malawi in 201516,<sup>35,36</sup> which were widely covered in international media at the time. The events that go unreported in EM-DAT are smaller, on average, in terms of the population affected and the damages caused. However, we show that such smaller, under-covered events have substantial overall impacts. More than a fifth of the population suffered production and income losses in the droughts in Malawi in 2009-2010 and in Mali in 2074, according to our micro-data estimates, while there is no coverage of these events in the EM-DAT for the same years. Overall, we estimate the total number of people affected by droughts or floods in all instances covered by the microdata is between 145 million and 170 million, more than 4 times higher than what is reported in the EM-DAT for the same periods and the same shocks.

The micro-data analysis suggests that the aggregate value of the disaster impacts on crop production is substantial. For the drought in Ethiopia in 2015-2016, the micro-data crop loss estimates are much larger than the total economic damage reported in the EM-DAT. For the 2014 floods in Niger, the estimated value of crop losses exceeds the total damage reported in the EM-DAT data by almost USD 78 million (in 2022 USD values). In the other years there is no damage estimate in EM-DAT, but our survey micro-data documents even some large disaster impacts, such as in Niger in 2011 and Ethiopia in 2018-2019 with estimated losses of USD 1.6 billion and USD 1.4 billion, respectively. Taken together, we estimate that across the countries and years captured in the microdata, there were USD 5.1 billion in drought and flood damages unaccounted for in the EM-DAT data (Table 18).

What explains these discrepancies? Disaster inventories such as EM-DAT and survey microdata differ in a number of meaningful ways. Most importantly, disaster inventories do not measure shock impacts themselves but instead aggregate data from government sources, humanitarian organizations, the media, and others. They therefore rely on the comprehensiveness and accuracy with which shocks due to natural hazards are covered by one or more of these sources.<sup>30,37</sup> Less salient events as well as those affecting marginalized population groups are less likely to be reported on and less likely to have detailed information on the affected population or economic and welfare impacts.<sup>37–40</sup> This is particularly acute in LMICs where the density of information for disaster repositories to draw on is much lower and a large share of damages is uninsured.<sup>30,37</sup> Shocks in LMICs in general and smaller events (in terms of intensity or the population affected) in particular are more likely to have incomplete or inaccurate information in disaster repositories or are not covered at all.<sup>30,37,41,42</sup> Microdata such as the LSMS-ISA measure shock impacts on smallholder farmers where they occur by asking farmers directly. They therefore do not suffer from the same limitations regarding the recording of smaller, less salient, or more localized shocks and their impacts as disaster repositories.

Smaller shocks or adverse climatic events may not be considered disasters as disasters suggest a minimum level of severity. For an event to be recorded in the inventory, the EM-DAT requires a minimum of 100 people to be affected (injured, homeless, in need of immediate assistance) or an official declaration of 7