The data is probably too hard to deal with but the data stored by most network monitoring applications is in what is called RRD for Round Robin Database. Cacti, zenos, mrtg, nmis, and many others all use the same method, RRD. RRD data can easily be examined with RRD Tool or Ddraw. The trouble is the dude takes RRD data and stores it in an XML format inside a database that is compressed by a zip algorithm as it is stored. So you would have to open the table, then find the device then find the RRD in the XML then extract it to a standard RRD format and save it.