Tim Fernholz wrote about some business research sponsored by DHL:

• The map above depicts the volume of phone calls between countries.
• The average international phone call travels over 4,000 km.
• The average person spends 152 minutes a year talking to somebody in a foreign country – up from 88 minutes in 2005.
• 7.7% of all international phone calls are from the US to Mexico and 3.2% are from the US to India.
• 41% of all calls go from developed countries to developing ones while just 9% go the other way.

Read more about popular non-US telephone connections, why this shows that the earth isn’t flat, and see an alternative depiction of the data above here.

Source: Quartz