Math formula's in maps

[Ammer]

HI,
I was wondering if anybody knows a way to add or substract values in maps?
I have a overview map with several submaps where we are running a number of hotspot servers.

My goal is to display the combined number of hotspot users on the overview map under the symbol of the submap.
Currently i am displaying the active users from the 3 hotspot servers this way:

active:{HGB01:hotspot.users.active.last(0)}+ {HGB02:hotspot.users.active.last(0)}+ {HGB03:hotspot.users.active.last(0)}+ {HGB04:hotspot.users.active.last(0)}

But it shows up "active 1+2+3" instead of "active 6"

Is there a way to add these results in the label section? or do i have to make a calculated item under the host group in order to display?

[steveboyson]

I'm not sure if it is implemented in 2.2.x, but in 2.0.x this cannot be done.

You may want to create a "calculated item" which sums up the required values.
Then use that item on your map as a label.