The history tab display all status changes for the host, like "Last State Change" in Hud, but for entire life of host.
One row for one day, the date on the left (1).
On the right :
- Top Top (2) : A summary of state changes for the day. Each status in percentage represented with gauges.
Bottom (3) : A list of all status ranges for the day.
For each range : 
In this detail list, context changes (flapping, avknowledge, downtime...) are also shown : 
Note that if there only one range, the detail list is not displayed : 
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