Wikipedia Lugol's page adds both I and KI percentages to get the overall percentage.
For example, "our" 5% would be listed as 15% on this page, both with identical concentrations.
Most of the rest of the industry only uses the Iodine content on the label (ignoring the KI percentage).
The UK Lugol's seems to use the Wikipedia method.
Additionally, they used 100% instead of the "75%" (76.45) for their KI to I conversion.
Kind of sloppy also, the percentages are a bit off within 2% or so.
In other words, this 3% Lugol's is really 1% the way J Crow (for example) labels theirs.
Also, the KI/I conversion could be adjusted using the 76.45 figure.
I have a small xcel spreadsheet which helps on all this if anyone is interested.
How have you been calculating, or measuring out your lugol's ??