Paul John (whisky) evaporation during aging, known as the angels' share, is also higher in India, at 10–12% per year, than in Scotland, where the annual evaporative loss is about 2%. This leaves a hogshead with only 150 bottles left in it, after three years, compared to around 350 in a Scotland. Michael John describes it this way, "Whisky matured at these temperatures simply cannot be aged for the kind of time expected with Scotch, even trying to mature our whisky for just 10 years would leave barely a bottle of liquid in the barrel. Fortunately, the heat actually speeds up the maturation
Barrel necessary elsewhere, whisky made elsewhere is usually aged in used barrels that previously contained American whisky (usually bourbon whisky). The typical bourbon barrel is in size, which is thus the "de facto" standard whisky barrel size worldwide. Some distillers transfer their whisky into different barrels to "finish" or add qualities to the final product. These finishing barrels frequently aged a different spirit (such as rum) or wine. Other distillers, particularly those producing Scotch, often disassemble five used bourbon barrels and reassemble them into four casks with different barrel ends for aging Scotch, creating a type of cask referred to as