Its an interesting quandry I suppose if you are a lease company. If you are trying to sell leases on a vehicle that is say 4 years into its product life cycle (ie maybe 2 years from being replaced by a new model) then the residuals are projected to be lower.... equally, at the start of the model cycle they are probably higher.
I wonder, do you just hope that the cycle balances it out or do you actually decrease the lease cost at the start of a model cycle and increase it over time until at the last minute you drop it because the end of life phase of the model is heavily discounted by the manufacturer (ie when the actual new model production dates are announced)?
(This crossed my mind as earlier I was reading about the idea of surge pricing in supermarkets!)