CPU Utilization Mod to XLM file

I am trying to monitor the CPU Utilization of a Application Firewall using the private enterprise MIB. I added a new resource monitor section in the opmanager_graphInfo.xml file, stopped and started opmanager. I added the resource monitor to the application firewall but no data. I did a test of the new resource monitor and it appended a .0 to the end of the OID. Why did the application append this suffix.

Monitor Name CPUUtilization
Protocol SNMP
OID .1.3.6.1.4.1.7118.3.1.25.1.1.2.18.47.99.108.117.115.116.101.114.47.99.105.115.108.97.98.110.99.52.0

I added the following section in the opmanager_graphInfo.xml file:

<DEFAULTGRAPH Name="NetContinuum-CPUUtilization">
<YAXISTEXT>Percentage</YAXISTEXT>
<DISPLAYNAME>CPU Utilization</DISPLAYNAME>
<name>CPUUtilization</name>
<Vendor>SNMP</Vendor>
<Monitor>Resource</Monitor>
<Description>Monitors the CPU Utilization based on NetContinuum SNMP MIB</Description>
<oid>.1.3.6.1.4.1.7118.3.1.25.1.1.2.18.47.99.108.117.115.116.101.114.47.99.105.115.108.97.98.110.99.52</oid>
<type>node</type>
<interval>900</interval>
<THRESHOLDENABLED>false</THRESHOLDENABLED>
</DEFAULTGRAPH>

Thanks in advance.
Jeff