VPN tunnel monitoring for Cisco ASA - graphs showing obscure results

Hi,

Regards VPN monitoring on an ASA 5545, I have found the following article below:-

http://thwack.solarwinds.com/docs/DOC-137039

Using Universal Device Poller I have created the four OID's & they appear to be graphing. The site to site VPN graph identifies the number of correct, current no. of VPN tunnels but there are consistent gaps in the graph. See below:

Also, the webvpn anyconnect graph displays no active users but logging onto the ASA there are at least 3 active users. See graph below:

Can anyone shed some light on why they don't appear to be graphing correctly?

Thanks.