G'day!
In the manual it's written that change function "Returns difference between last and previous values". Unfortunately for me it's not like that due to unknown reason

Here is the glitchy trigger (There is no space in "change" word below, it's the forum engine who adds it):
Code:

Name PSTN channels are lost [

{HOSTNAME}

::TS1]
Expession

{jboss_cs_t:jmx_trunk_group_total_channels_ts1.change(0)}

<0

Here is the extract from "Latest data":
---------------------------------------
somehost.company.com: Total channels on TS1
Timestamp Value
... ... ...
2007.Oct.04 07:45:16 392
2007.Oct.04 07:40:18 368
2007.Oct.04 07:37:11 392
2007.Oct.04 07:35:15 392
2007.Oct.04 07:31:18 392
2007.Oct.04 07:30:13 368
2007.Oct.04 07:27:19 368
2007.Oct.04 07:25:19 392
---------------------------------------

As you see, the difference between last(it's 368) and previous (392) was 368-392=-24 which is definitely < 0 But the trigger wasn't activated at the moments I marked red.

So, did I make any mistake or it's a known problem?
Thanks in advance!