**I would like to sum over the index j.**

Assume you have 100 time series x(j) and you wish to sum over(j):

y = sum(j, x(j))

with the objective to get the following ratio:

contribution(j) = x(j) / y

This in Eviews 7.2 does not work

for !j = 1 to 100

scalar y = @sum(j,x_{!j})

next