Popularity of IUDs

If the continuation rate for IUDs is higher that similar rates for oral contraceptives or injectables as mentioned in the essentials knowledge section and "Approximately 75 percent to 85 percent of women who choose the IUD keep it for at least one year," why isn't the IUD a more popular method? One would think that method satisfaction would have a snowball effect on the popularity of the method. Is there any recent survey evidence to show that IUDs are becoming more popular? If not, perhaps we should spend our resources and time on other methods?