Introduce new trigger function to detect recessions in a constantly growing progression

Hi,

Would be nice to have a trigger function that would count the number of recessions in a constantly growing progression of values.

Something like:
downturns(/host/item,(sec|#num)<:time shift>)

One simplest example of it's use would be to count the number of particular server reboots.
For example:
downturns(/host/system.uptime,24h) = 4 – fire when server has been rebooted 4 times per day according to system uptime.
Now it's only possible using calculated items which require update interval/history lookup period on item level but in some cases it's required to be alerted right at the time when a new uptime value has been received.

Other use-cases could be:

• detect how many times global BGP routing table had degraded
• detect how many times per day an asset has fallen at an exchange
• etc., probably much more for very specific use cases

Kind regards,
Sergey