Update 6: Shield preview, protection level vs cost

Before you add a Shield, the Shield page now shows a small table: how much protection you would get at 5%, 10% and 15% below today's price, and what each costs. For each level it shows the listed strike, the estimated cost now, the cost per day, the cost over 7 and 30 days, and the price below which it pays off. If no strike is listed near a level, it says so. The table follows the number of units you type, and "Choose" picks that level for you. The exact amount is still quoted before you confirm.