MRTG and CPU usage

Juniper Netscreen CPU utilization OID 1.3.6.1.4.1.3224.16.1.4.0

Target[10.50.28.5_cpu]:.1.3.6.1.4.1.3224.16.1.4.0&.1.3.6.1.4.1.3224.16.1.4.0:public@10.50.28.5:
SetEnv[10.50.28.5_cpu]: MRTG_INT_IP="10.50.28.5"
MaxBytes[10.50.28.5_cpu]: 100
Title[10.50.28.5_cpu]: CPU Utilization
PageTop[10.50.28.5_cpu]: CPU Utilization -- netscreen25
Options[10.50.28.5_cpu]: growright,gauge,integer,nopercent
Unscaled[10.50.28.5_cpu]: dwym
YLegend[10.50.28.5_cpu]: CPU load
ShortLegend[10.50.28.5_cpu]: CPU Load
Legend1[10.50.28.5_cpu]: CPU Load
Legend2[10.50.28.5_cpu]: CPU Load
LegendO[10.50.28.5_cpu]:

Foundry's CPU utilization OID 1.3.6.1.4.1.1991.1.1.2.11.1.1.4
There is a catch - Foundry reports utilization in 1/100 of the procent, so number 820 means 8.2%. I have Fondry ServerIron 450 with 1 management CPU and 3 CPUs on Web Switching module and wanted to know 5 min. average for management CPU:

Target[10.50.254.5_cpu]: 1.3.6.1.4.1.1991.1.1.2.11.1.1.4.1.1.300&1.3.6.1.4.1.1991.1.1.2.11.1.1.4.1.1.300:public@10.50.254.5:::::2
SetEnv[10.50.254.5_cpu]: MRTG_INT_IP="10.50.254.5"
MaxBytes[10.50.254.5_cpu]: 10000
Title[10.50.254.5_cpu]: SI450 Management CPU Utilization
PageTop[10.50.254.5_cpu]: Management CPU Utilization -- nwklb01-a
Options[10.50.254.5_cpu]: growright,gauge,integer
#Unscaled[10.50.254.5_cpu]: dwym
YLegend[10.50.254.5_cpu]: 1/100 percent
ShortLegend[10.50.254.5_cpu]: CPU Load
Legend1[10.50.254.5_cpu]: Mangemnt CPU 5min average
LegendO[10.50.254.5_cpu]:

OIDs for WSM CPUs 1-3: 1.3.6.1.4.1.1991.1.1.2.11.1.1.4.[2-4].300

PS: my community string is not really "public"