The purpose of these price-control measures is, in short, to stop the price of units available at auction getting either too low or too high. Exactly where the clearing price falls, within the parameters of the price floor and cost containment reserve, will be determined by a range of other factors, not least of which is the activity on the secondary market. The secondary market is where trades take place between various buyers and sellers, through which we get a sense of market opinion about the current value of a New Zealand unit. Secondary markets are crucial to the functioning of the emissions trading scheme, not least because they provide a means for participants to sell surplus units, which creates a powerful incentive to reduce emissions. Stability, then, like in any other market, is crucial. Its absence risks undermining confidence that the cost of population remains at a certain level, which could all but eliminate the price incentive to reduce emissions and make it much harder for participants to make long-term investment decisions. This bill will provide for that stability through the introduction of a reserve price to ETS auctions.