When a new product is put on the market, It is difficult to say whether a generic manufacturer is going to produce an equivalent in 12 or 14 years. In Canada, the average exclusivity period for brand-name products is more like 12 to 14 years, not 5 to 9 years as my colleagues have mentioned. If a product is on the market when its patent expires, the generic product manufacturers will decide if they are interested in producing it, and can still make a profit while selling it at half the price.
On May 8th, 2008. See this statement in context.