Dear Chandrasekhar.:
Looking at Apache (IBM HTTPD) Metrics,we get the following:
CA APM for Web Servers Metrics - CA Application Performance Management - 10.5 - CA Technologies Documentation
For more information about Apache-based metrics that can be sent , see https://httpd.apache.org/docs/2.4/mod/mod_status.html
Concurrent users is not on that list.
This was also covered in
-- Apache-based web servers will provide that info in the extended info stats page,
I hope this info is helpful. This question is answered as much as it can be