Please check for the below mentioned points to resolve this issue.
1. The interface speed is not set right and NetFlow Analyzer uses the default speed of 1 Mbps (which may not be the correct interface speed).
Most of the analyzers determine the interface speed if you set the appropriate SNMP Port and Community for the router on the Analyzer.
2. The active timeout has not been set to 1 minute on the routing / switching device. You can use the command 'ip flow-cache timeout active 1' to set the active timeout to 1 minute on your router.
3. Non dedicated burstable bandwidth, where the ISP allows you to use over the allocated bandwidth depending on the other customers sharing that link
4. Also, please check if there is any application name being listed as 'ESP_app'. The analyzer may double count your traffic.
Thanks
Raj
ME NetFlow Analyzer
www.netflowanalyzer.com