Guidelines regarding the "zero":
0 series - no hatched '0'
1 series - no hatched '0'
2 series - no hatched '0' until 27xxxxx sub series
3 series - hatched '0'
4 series - hatched '0'
5 series - hatched '0' in the early 5 sub series (50xxxxx to 51xxxxx). No hatched '0' in the mid 5 sub series (52xxxxx to 56xxxxx) until the 57xxxxx sub series when the hologram sticker changed to the present style.
6 series - hatched '0'
7 series - hatched '0'
8 series - hatched '0'
9 series - hatched '0'
10 series - hatched '0'
11 series - hatched '0'
12 series - hatched '0'