IP SLA templates against real values

[petpet]

HI ,
I'm using IP SLA templates to monitoring Cisco SLA values.
However , some I'm not sure if the values displayed and counted are correct according to Cisco CLI statistics.
Did anybody check it in your own system ?
Here is the example:

the output from the Cisco cli is :

sh ip sla statistics aggregated 1 details

Round Trip Time (RTT) for Index 1
Start Time Index: 13:54:55.360 CET Thu Nov 18 2010
Type of operation: jitter
Jitter time milliseconds
Number of SD Jitter Samples: 5618
Number of DS Jitter Samples: 5618
Source to Destination Jitter Min/Avg/Max: 0/2/63 ms
Destination to Source Jitter Min/Avg/Max: 0/2/114 ms
Source to destination positive jitter Min/Avg/Max: 1/2/63 ms
Source to destination negative jitter Min/Avg/Max: 1/2/28 ms
Destination to Source positive jitter Min/Avg/Max: 1/2/114 ms
Destination to Source negative jitter Min/Avg/Max: 1/1/111 ms

As you can see the values are quite different.
I'm using packet-size 200 bytes, frequency is 20 seconds, so the values should be similar

Thanks for any hint
peter