About 20% of the "Public Figures" list is for this reason..
Anchor,
I understand you may not be free to say from where this figure is based, but are you personally confident that it is reasonably accurate?
As LionHeart has said, most individuals are fairly savvy about the consequences of stating formally (to DoS staff) they are renouncing for any type of general
tax reasons.
I understand the question,
"why are you renouncing" is not asked at the London Embassy, although there are reports of those elsewhere in the world being asked the question at some Embassy/Consulates at present.
EDIT: Sorry, the penny may have dropped, but did you mean by "Public Figures" known personalities, such as Legislators, politicians, etc throughout the world?