will wane over time and that will be l will wane over time and that will be a gradual will wane over time and that will be a gradual decrease. will wane over time and that will be a gradual decrease. it will wane over time and that will be a gradual decrease. it does- will wane over time and that will be a gradual decrease. it does not- will wane over time and that will be| a gradual decrease. it does not stay at a particular a gradual decrease. it does not stay at a particular level a gradual decrease. it does not stay at a particular level for a gradual decrease. it does not stay at a particular level for five - a gradual decrease. it does not stay at a particular level for five or- at a particular level for five or six months at a particular level for five or six months and at a particular level for five or six months and then - at a particular level for five or| six months and then suddenly at a particular level for five or- six months and then suddenly drop off a cliff