completed responses have been met in each governorate aside from the island of Soccatra. The number of minimum responses per governorate are determined by the governorate’s share of the total population. The number of respondents surveyed each month is approximately 2400.<sup>8</sup> The survey is a rolling panel, where the call center acquired a list of 2400 phone numbers that answered the survey in the initial month via random digit dialing, subject to the governoratelevel targets mentioned above. In the second month, the same 2400 phone numbers are contacted for an identical survey. Of these 2400, approximately 400 on average will not be able to be reached and will have to be replaced with a household from the same governorate via random digit dialing, and approximately 200 will not respond for two months in a row. However, those that are not reached will continue to be listed in the bank of possible phone numbers to be tried each month and will only be dropped from the survey completely if they have been tried to be contacted and not completed a survey for three straight rounds.<sup>9</sup> Every month, the survey collects information necessary to construct the Food Consumption Score (FCS)<sup>10</sup> , information on food coping strategies necessary to construct the Reduced Coping Strategy Index (rCSI)<sup>11</sup> , information on whether the household received food assistance in the past month, and information on the location of households (governorate and district). Other survey modules have been inserted in a subset of monthly surveys, including modules on displacement status and the type of housing in which the household lives.<sup>12</sup> Although the survey reaches 2400 households each month, the household-level data is not publicly available. However, the WFP publicly shares each month the governorate-level averages and confidence intervals of all key variables collected<sup>13</sup> , and these monthly governorate-level estimates are used in the empirical analysis to analyze changes in food assistance and food access following the 2017 IPC announcement.<sup>14</sup> We further merge the mVAM data with data on violence using data from the Armed Conflict Location & Event Data Project (ACLED) on the number of people killed in each governorate each month to be used as control variables.

However, there are important caveats to note about the data. First, it is likely that there is a significant amount of district-level variation, local factors, and household factors that impact both food assistance and food access. However, we are unable to analyze these factors in the present analysis given the data is publicly available at only the governorate level.

Second, the survey can only be representative of the mobile phone-using population following the beginning of the conflict. Although it is difficult to identify exactly how access to mobile phones have changed since the start of the conflict, all evidence suggests that access has remained

> 8See Appendix 2 for the number of responses by governorate. 9The WFP is unable to observe whether a phone number exists or not in the random digit dialing procedure, and thus we are unable to identify the share of active phone numbers that do not respond to the survey.

> 10The FCS is a weighted count of the number of days a household consumed particular food groups in the past week. A higher FCS is associated with better food access.

> 11The rCSI is a weighted count of the number of times the household has relied on food coping strategies in the past week. A higher rCSI is associated with a worse food access.

> 12See Appendix 3 for the variable definitions used in the survey, and for an example of one of the monthly questionnaires.

> 13They also share the estimates and confidence levels of national-level estimates as well.

> 14An example of a similar empirical strategy is Dell et al. (2012), which use annual GDP estimates to demonstrate a relationship between well-being and temperature.

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