Interdependent Series

Hi

I am trying to create series which depend on each other, These are the 2 types of series blocks I'm trying to generate.

Example 1:
Z(0) = initial Z = 0.1
Y= alpha - 2*Z
Z = Z(-1)+Y(-1)

When I code the above using frml, an error message "circular reference" is displayed. Given the initial value, the interdependent series should be able to solve. We are trying to avoid using "model" as we have many sets of variables that are interdependent.

Example 2:
For series W, it has one formula for smpl 1980-1990 and another formula from 1990-2015. Hence, I know frml cannot be used. But how could I code this please?

smpl 1990 2015
W = V/E
We have data for V and E series from 1990-2015. So we can solve for W.

smpl 1980 1989
W = W(+1) + 2*S - 0.5*F where S and F are series.
By right, this should be solvable and since we have W(1990) from the previous formula. However, when i try this, I get NA for the entire W series.


We are trying to shift our Excel spreadsheets into EVIEWS and would appreciate any advise on how we can convert the series described above.

Thank you for any help!

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