wall-wart cable

[KM3K]

I'm in the process of cataloging all my wall-warts into a spreadsheet (so that I know how many hundreds of these things there are in the house ; seems like every room has at least several).
I noticed that everyone so far has marking on one of the two DC-leads or the entire lead is white.
Just out of curiosity, I'd like to know, "Is the marked-lead the positive or the negative polarity?"
73 Jerry KM3K   FN10je

[N3OX]

I would say in most of the ones I have, the marked lead is positive.

Unfortunately, even though it's sort of rare, I have come across ones with the marked lead negative, so  they need to be checked.

73
Dan