Provided it has not been stored at very extreme temperatures or exposed to UV light, I think PVC will probably outlive all of us in terms of its properties! PVC cables do not come with a specified shelf life. These days (but not back then) they have the date of manufacture written on them.After that length of time, is the pvc still sound ? Does cable have a shelf life ? The short bit of pvc that I stripped from the copper core was flexible and sound and the reels have been kept in a dry building for all these years.
Kind Regards, John