Email notification should contain about duration in normal/triggered state

[xmacan]

Alert, warning and restoral emails contains a lot of variables:

A Threshold has returned to normal status.

Device: <DESCRIPTION> (<HOSTNAME>)
URL: <URL>
Message: <SUBJECT>

<GRAPH>

I would like to have there information like: Breached state duration : 2 hours or Normal state duration: 1 years and 5 weeks....