NGINX RTMP STATS: Deviation between number of clients in XML and actual #streams

[PrinceofTexas]

We are currently testing NGINX RTMP for live and VoD streaming. We did benchmark load testing
and analyzed the output of the Stats/XML. We sent 400 streams to the media server and
measured 800mbps in Zabbix. We take in the NGINX Stat the number of clients as metric
for number of connections. What we don't underderstand is that we send/see 400 streams (800mbps) on Zabbix,
but NGINX Stat/XML reports only 50 streams
1. Which metric in the NGINX RTMP STATS/XML stands for the number of streams?
2. Can somebody help me understand the deviation?