For example, it fully ignores the large transfer of money from the federal government to government employees in Blue eastern seaboard states. The fed is a huge employer in many blue states. See also other methodological criticisms in this thread (e.g., its criteria for dependency is just wrong -- should be absolute Fed dollars spend per capita, but is instead percentage of spend). It also ignores the benefits to higher fed tax-paying states of having the lower-paying states in the union, which are not captured solely in tax flows.