GDP is value created within the boundaries of a country.
GNP is value created by nationals/entities of a country.
GNP is value created by nationals/entities of a country.

For the longest time, the U.S. insisted on trumpeting the GNP number. Wasn't till communism "fell" that we moved the GDP number in everything. Still, for the longest time, all of the newspapers focused on nominal GDP growth. It wasn't until the mid-90s that everything was standardized to real GDP growth.
Over the last 10 years, real GNP and GDP were pretty much in lock-step. ~39% growth.
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