I took delivery of the first of a pair of new 60m ropes the other day. In the information pamphlet it said that you can loose up to 10% of the length of the rope with use!
Which got me thinking.
As I have access to a cordage meter I decided to measure it and unused it's 63m near enough exactly. I also measured an old rope that I bought as 50m x 10.5mm which is now 48.2m x fatter than 10.5mm.
Food for thought. That's all folks.