If your Y variable depends only on stationary level or similar time (t) then you can use static. That means for every Y you find the relationship with the corresponding time inflation Y t = B * Inflation t
If your variable depends on past steps of time, then you should use the auto regressive when Y t = B1 * Inflation t + B2 * Inflation t-1
If you don't know your data well, you can apply both of them and find the lower RMSE or BIC