What is the percent distribution of first letters in last names in the US?

A 3.75%
B 8.96%
C 6.38%
D 5.65%
E 2.03%
F 3.63%
G 5.34%
H 5.59%
I 0.76%
J 1.36%
K 5.70%
L 5.24%
M 8.28%
N 2.13%
O 1.63%
P 5.27%
Q 0.26%
R 4.80%
S 10.93%
T 3.88%
U 0.47%
V 2.55%
W 3.46%
X 0.02%
Y 0.65%
Z 1.29%

per the US 2000 Census table of all valid last names appearing the 100 or more times (covering 90% of responses).