Why is Followed Linking Root Domains higher than External Followed Links?

[Silktide]

Surely there must be at least one external link for each linking root domain?

Some results for smaller sites give a higher number of domains linking in than incoming links - e.g. www.forbesandsawyer.co.uk

Under Subdomain metrics:

External Followed Links - 1

Followed Linking Root Domains - 2

Surely 2 root domains would mean AT LEAST 2 external followed links?

Thanks,

Andrew

[Cyrus-Shepard]

There are some strange outlier instances, but in this case a domain that links to itself counts as a linking domain. (since it's entirely possible to have a domain not link to itself, we have to count it when it does.)

So, a domain that links only to itself, with no other links, would have 1 linking root domain and 0 external links.

[Silktide]

I kind-of guessed that, but I wanted to make sure.

I think it would be good if there was more help text next to each metric (or perhaps on hover) explaining this as it doesn't seem obvious at first.