diff --git a/doc/arm/reference.rst b/doc/arm/reference.rst
index cf1ba1b12c..9b14b0cf00 100644
--- a/doc/arm/reference.rst
+++ b/doc/arm/reference.rst
@@ -8404,3 +8404,6 @@ exceptions are noted in the descriptions.
 
 ``<TYPE>RecvErr``
     This indicates the number of errors in socket receive operations, including errors of send operations on a connected UDP socket, notified by an ICMP error message.
+
+``TCP4Clients``/``TCP6Clients``
+    This indicates the number of IPv4/IPv6 clients currently connected over TCP.