Convergence to new steady state

Dear Prof.,

My question concerns whether there is a sensible length of time for a model to converge to its new steady state.
I am modifying an existing RBC model in a published paper. In the existing model, following the permanent shocks (to market regulation) I am also examining, the economy takes about 168-169 periods (periods are interpreted as quarters) to reach its new steady state.

With my modification it takes over twice the amount of time (between 425 and 491 periods). I am not sure whether this would be considered too long. Does it appear unreasonable for a model to take this long to reach its new steady state following a permanent shock?

Thanks in advance for your help.

Convergence to a steady state is always only asymptotic, i.e. will happen in infinite time. Your question refers to how quickly we should expect most of the distance to be gone. 125 years as in your case sounds like it’s on the high end. However, capital dynamics can be really slow.