Frank V. Cespedes: It's specific to the business. Think about it this way: If you look at most retailers, there's a reason we use the phrase 'supermarket margins'. They're working on margins typically of 1-4%. So when COGS goes up a percentage point, that's a big deal in that business. On the other hand, there are software businesses where margins are in excess of 50%, so the cost increase threshold is obviously going to be different.