Viewer statistics are found in the Broadcast Panel section of the CWM control panel.
The Current Viewers count shows a real-time number of viewers currently connected to your stream. This number is totaled up of how many "connections" are made to your stream. So it is possible for 1 ip address to be counted multiple times if there are multiple devices connected from the same ip.
The Viewer History chart shows a count of how many unique web viewers and mobile viewers that have connected to your stream. This chart is broken down by month, then by day. You can also look up counts from previous months using this chart. These numbers are totaled up based on unique ip addresses.