Information about all failures detected is recorded in a database (time of finding, duration, failure type) and there is unlimited access to it. In other words, the history is never deleted unless you wish to have it purged.
The history of unavailability events is presented as tables (date and time of finding, duration, failure type) and charts (number of events and the total unavailability time). Time period presented in the history is by default the last 30 days but you can change this any time or even display the whole history as one chart.
One click is enough to export history data to XLS file so that they can be analyzed further.
What makes it easier to have an overall look at the time period which is just being presented is the totalling module. It displays the total number of failures, total unavailability time and the uptime/downtime in percentages.