common log format...unresolved hosts?

Bob Cunningham (
Thu, 13 Apr 1995 15:14:22 +0500

In re log analysis, we fairly consistently see about 26%-27% of
browing IP addresses showing up unresolved.

Does that much of the Internet indeed have broken DNS reverse lookups,
or is that high a percentage some sort of artifact of how the httpd
server (NCSA httpd in our case) does logging?