These base Type is the same as in the Muggle World:

0
A
B
AB

Addtional / Magic Type (based on the wizards / witches powerlevel):
[Credit to Viscountess Babbles-On for the Blood-Magic-Type - it's her's and I took it from her story: The blood connection]
I my have altered some things a bit but please don't flame me, I'm just borrowing this for my own story (It won't have major importance there).

Sigma		The strongest type (only powerful magical beings have this)
Theta		The second strongest type (powerful people have this)
Delta		The middle type (the most common)
Gamma		The second weakest type (the weaker magicals have this)
Alpha		The weakest type (Squibs have this)

How common are the Types?

Sigma (>1 % out of 1000):
	0 = 02 %
	A = 45 %
	B = 36 %
	AB = 17 %
Theta (>15 % out of 1000):
	0 = 35 %
	A = 27 %
	B = 29 %
	AB = 09 %
Delta (~ 68% out of 1000):
	0 = 40 %
	A = 35 %
	B = 15 %
	AB = 10 %
Gamma (~15 % out of 1000):
	0 = 54 %
	A = 26 %
	B = 15 %
	AB = 05 %
Alpha (~1 % out of 1000):
	0 = 45 %
	A = 25 %
	B = 14 %
	AB = 06 %