A key feature of this indicator is that data is available at polling station level.
In the UK the Representation of the People Act 1983 requires polling stations to combine votes with at least one additional polling station before any counting occurs. This is to protect the identity of voters in the event that a candidate receives a low number of votes.
I think in the interests of transparency it is worth having this information as a note on the relevant data page. Otherwise a reader, who could be from any part of the world, will only be getting a partial view of the situation. Presumably they can then make their own judgement if they regard this a positive or negative state of affairs?