The chart is potentially misleading because it only focuses upon the dimension of transfer when markets can be based upon speed. South Korea oftentimes has tiers of data based around speed rather than a cap or aportionment, which is part of why its cheapest 1 GB is less than 1/4 of what it is in the US but seems comparable. My point is mostly that level of service is another dimension that is hidden from the chart that should be quantified to better understand the underlying trends.