Issue with dataset: The Great Acceleration: Trajectory of the Anthropocene

Start with the linked Great Acceleration dataset and inspect socioeconomic.csv, focusing on the Real GDP rows for 1820–1830. Compare those values with the referenced IGBP XLSX data and determine the expected figures; done means the 1821–1829 discontinuity is resolved or its source is clearly documented.

Dataset: The Great Acceleration: Trajectory of the Anthropocene
URL: https://datahub.io/climate-and-environment/great-acceleration

Describe the issue:
In "socioeconomic.csv"

The Real GDP data reported between 1821 and 1829 cannot be correct.

Global GDP was 0.46 Trillion USD in 1820
and was below 0.1 Trillion USD for the next 9 years,
then up to 0.25 Trillion USD.

I checked the IGBP XLSX data, it has the same problem.

year,indicator_id,indicator,unit,world,oecd,brics,rest,https://r2.datahub.io/cmmt24bjv000vjl04yxn8l104/main/raw/data/socioeconomic.csv

1750,real-gdp,Real GDP,trillion USD (2005),0.3518815529384608,0.2538311479244052,0.07028288199597246,0.027767523018083155
1820,real-gdp,Real GDP,trillion USD (2005),0.4696838368193744,0.33828407462954063,0.09316028738502426,0.03823947480480956

1821,real-gdp,Real GDP,trillion USD (2005),0.07738851807079479,0.07738851807079479,,
1822,real-gdp,Real GDP,trillion USD (2005),0.07548215263671115,0.07548215263671115,,
1823,real-gdp,Real GDP,trillion USD (2005),0.07830950233335374,0.07830950233335374,,
1824,real-gdp,Real GDP,trillion USD (2005),0.08098824304749987,0.08098824304749987,,
1825,real-gdp,Real GDP,trillion USD (2005),0.07874698291054305,0.07874698291054305,,
1826,real-gdp,Real GDP,trillion USD (2005),0.08030815901194939,0.08030815901194939,,
1827,real-gdp,Real GDP,trillion USD (2005),0.08005419738359432,0.08005419738359432,,
1828,real-gdp,Real GDP,trillion USD (2005),0.08099784163059232,0.08099784163059232,,
1829,real-gdp,Real GDP,trillion USD (2005),0.08289264384416159,0.08289264384416159,,

1830,real-gdp,Real GDP,trillion USD (2005),0.2532979227403575,0.2532979227403575,,