Your article seems to be restricted to Mahayana Buddhism, as practiced in India and parts of China. It ignores the Theravada branch that is prevalent in Sri-Lanka, Thailand, Laos and Cambodia.
The Pew Research Center's analysis was a global analysis which grouped Buddhism into three categories: Mahayana, Theravada, and Vajrayana. I believe that this article reflected that analysis.
Your article seems to be restricted to Mahayana Buddhism, as practiced in India and parts of China. It ignores the Theravada branch that is prevalent in Sri-Lanka, Thailand, Laos and Cambodia.
The Pew Research Center's analysis was a global analysis which grouped Buddhism into three categories: Mahayana, Theravada, and Vajrayana. I believe that this article reflected that analysis.