You can track the alert status as a metric:
*SuperDomain*|Custom Metric Host (Virtual)|Custom Metric Process (Virtual)|Custom Metric Agent (Virtual)|Alerts|<management module name>|<alert name>
0 = no data (alert is configured by metric grouping is not matching anything)
1 = normal (no threshold breeched)
2 = caution level
3 = danger level
Inactive alerts will not appear
Maybe you can track from there any changes in the graph any scenario which indicates a alert condition was raised, like from 1 to 2, 1 to 3 or 2 to 3.
Using a JavaScript calculator you might be able to report a metric per alert per day, just another suggestion, though I'm not sure how well Javascripts work on a cumulative 24-hour basis