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The API attribute total_msg_impressions represents the number of impressions for a single average impressions per spot instanceper hour. To convert from average impressions from per spot instanceper hour (i.e., total_msg_impressions) to impressions per spot per hour, we multiply the API value 'total_msg_impressions' by the number of times a spot is displayed per hour. In the above example for the digital sign, we would multiply total_msg_impressions by 60 (i.e., one time a minute or 60 times an hour).
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