Pirelli 'P Zero' font question

I was wondering when Pirelli changed the 'P Zero' font that they use on their tires. It seems as though they switched from this font that looks like times new roman to a more modern, italicized, sans serif font with 'P Zero' appearing much larger on the tires. I was browsing listings of used Ferraris online and notice quite a few with this serif font (but date codes not legible in the photos), and was curious when the change was made, so I can estimate the minimum age of one of these serif font tires.