[Antennas] Insul wire vs bare ant wire length

[Nelson Wittstock]

I recall reading that insulated wire for antennas needs to be a different
length than bare wire but don't recall how much difference or which way.  I
have wire ready for a pennant antenna but it is insulated and stripping 70+
feet of wire does not sound like fun.  By what factor do I need to adjust
the length or would it be better to just go ahead and start stripping <the
wire that is>?

Nelson, K8DJC