Simulink is it possible to have different delay at different simulation time?

[poster]

I am building a delay system like this:

Simulation time is from 2005 to 2035 and the time step is fixed to 1.

What I want to do is to have different delay time at different time.

For instance, in the first year, no delay; but in the second year, there is 1 time step delay; in the third year, there are 2 time steps delay.

However, when I ran this model, I got this result:

In scope 2 are the signals, and in Scope are: upper is supposed to be the sum of the two signals after delayed, and the bottom is the sum of the signals.

But I cannot see the delayed signal.

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