Definitely. The majority U.S companies will only target the U.S and maybe Canada. The reason is plain and simple. India and China visitors don't shop online. They're too poor. Most probably don't even have a credit card. Spending advertising dollars in India or China is only good for branding purposes. If the majority of your traffic is from these countries your epc will be very low. I would say at least 3 to 5 times lower.