diff --git a/man7/tcp.7 b/man7/tcp.7
index 2a1ad135f..94ab35608 100644
--- a/man7/tcp.7
+++ b/man7/tcp.7
@@ -472,7 +472,7 @@ In Linux 2.2, the default value was 180.
 .\"
 .\" The following is from 2.6.12: Documentation/networking/ip-sysctl.txt
 .TP
-.IR tcp_frto " (integer; default: 0; since Linux 2.4.21/2.6)"
+.IR tcp_frto " (integer; default: see below; since Linux 2.4.21/2.6)"
 .\" Since 2.4.21/2.5.43
 Enable F-RTO, an enhanced recovery algorithm for TCP retransmission
 timeouts (RTOs).
@@ -485,13 +485,16 @@ This file can have one of the following values:
 .RS
 .IP 0 3
 Disabled.
+This was the default up to and including Linux 2.6.23.
 .IP 1
 The basic version F-RTO algorithm is enabled.
 .IP 2
+.\" commit c96fd3d461fa495400df24be3b3b66f0e0b152f9
 Enable SACK-enhanced F-RTO if flow uses SACK.
 The basic version can be used also when
 SACK is in use though in that case scenario(s) exists where F-RTO
 interacts badly with the packet counting of the SACK-enabled TCP flow.
+This value is the default since Linux 2.6.24.
 .RE
 .IP
 Before Linux 2.6.22, this parameter was a Boolean value,