Why does a profile with zero counts and zero base counts yield an Index value of 100?

Profiles will yield an Index value of 100 instead of zero because an Index of 100 is our baseline, indicating that segment presence in an area reflects its presence in a benchmark. This is also the case when there is zero count and zero base count.

An Index of zero is meant to reflect situations where there is no segment presence in an area but that segment does exist in the selected benchmark.