Looping over an alpha series

[caburdick]

How can I determine the length of an alpha series so that I can loop over it's elements.

I have a list of states and would like to loop over the list:

alpha mystates
alpha(1) = "ny"
alpha(2) = "tx"

for !i = 1 to length(mystates)
%state = mystate(!i)
Do state specific stuff
next !i

How do I determine length(mystates)?