F5 BigIP Traffic Mgmt CPU Util Custom Monitor

Has anyone sucessfully created a custom monitor for the TM CPU Util on a F5 BigIp. According to the F5 docs, the TMM CPU Util is calculated as follows:

TMM CPU Usage = ((<DeltaTmTotalCycles> - (<DeltaTmIdleCycles> + <DeltaTmSleepCycles>)) / <DeltaTmTotalCycles>) *100

So I tried the following custom graph. However, I was not able to add it to a device.

<CUSTOMGRAPH Name="TMM CPU Util">
<YAXISTEXT>(%)</YAXISTEXT>
<DISPLAYNAME>TMM CPU Util</DISPLAYNAME>
<name>TM CPU Util</name>
<oid>( (.1.3.6.1.4.1.3375.2.1.1.2.1.41/$DELTA_TIME) - ( (.1.3.6.1.4.1.3375.2.1.1.2.1.42/$DELTA_TIME) + (.1.3.6.1.4.1.3375.2.1.1.2.1.43/$DELTA_TIME) ) *100)/(.1.3.6.1.4.1.3375.2.1.1.2.1.41/$DELTA_TIME) </oid>
<type>node</type>
<timeAvg></timeAvg>
<interval>300</interval>
<THRESHOLDENABLED>false</THRESHOLDENABLED>
<FAILURETHRESHOLD>1</FAILURETHRESHOLD>
</CUSTOMGRAPH>

Where the OIDs are defined as:
.1.3.6.1.4.1.3375.2.1.1.2.1.41 = sysSatTmTotalCycles (counter64)
.1.3.6.1.4.1.3375.2.1.1.2.1.42 = sysStatTmIdleCycles (counter64)
.1.3.6.1.4.1.3375.2.1.1.2.1.43 = sysStatTmSleepCycles (counter64)