Is there any difference in these paint codes?

Mine is a B536PX, but I've also seen B536P as Royal Blue Pearl and am curious what the difference is.

Are they the same exact colors, just different years?

 

I couldn't find a pattern with years.
looking at google image search for either or paint codes, the door jam sticker pops up.
reading the door jam stickers, PX is found on earlier 05-06 cars, but then have seen them for '10+ cars.
P is found on '06 - '10+ ...
Couldn't find a rhyme or reason why some cars use P and some cars use PX

 

It looks like the OP is from a European country so the X could mean Export.