"GDP measured in constant 2021 international dollars, adjusted for purchasing power parity (PPP) to account for differences in the cost of goods and services across countries"

Meh, idk what magic maths they pull, but any other sources I find do not corroborate their graph.

https://www.researchgate.net/publication/352708343/figure/fi...

https://dimiter.eu/Visualizations_files/cee/gdppc_country.pn...

that is a graph of growth, but they started from different baselines, e.g. Hungary was famously known as "the happiest barrack in the communist camp".

Slovakia and Hungary have trailed % growth compared to Poland, but they are far richer countries now that they were 20 years ago, and the GDP per capita for Poland, Hungary, and Slovakia is quite close to each other[0].

I'm not trying to say Poland didn't do well, it did! I'm just saying the advantages of being in the EU outweigh any national merit by a lot, which should be quite self evident.

[0] GDP, nominal, per capita: 31,336 / 28,430 / 31,242 https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nomi...