We have updated the definition (and calculation) of the Exits Before Video Start metric in the Data Monitoring API and Dashboard.
Previously, the EBVS metric in Monitoring used a population of the total number of concurrent viewers (CCV) at that time. This resulted in a metric that was often suppressed to very low percentages, making it difficult to track trends easily.
The updated EBVS metric in Monitoring is based on the population of viewers attempting to start playback during this time. Now, EBVS in Monitoring equates to the percentage of viewers trying to start playback that end up exiting before playback begins. We believe this metric is much more useful for surfacing issues in real time.