I'd like to show current data on a map.

Using a macro like this, allows:

The data alone is nice, but I'd also like to know when it is from, so it reads like "220.3 (12.12.2012)". I'm aware this could be difficult, as I won't not necessarily use last(0).

This functionality is particularly interesting for items that became disabled. Looking at the map, you'd never notice flawed data stemming from such an item, last polled 2 weeks ago without notice.