13% of the growth of Polish GDP in 2013-2018 was generated by Ukrainians

The Polish economy grew by 0.5 percentage points faster each year thanks to the work of immigrants from Ukraine, according to a new study of Polish scientists working at the Warsaw School of Economics and the National Bank of Poland.
Since 2014, Poland has witnessed an unprecedented inflow of immigrant workers from Ukraine. Combined with the strong demand for labor, this sharp increase in labor supply has made a significant contribution to Poland's economic growth shows an article published in the scientific quarterly Review of World Economics, by Polish scientists Dr.Paweł Strzelecki, Prof. Jakub Growiec, and Dr. Robert Wyszyński. Interestingly, this contribution has so far remained largely unaccounted for in official data.
As their research showed, the influx of workers from Ukraine increased the effective labor supply in Poland in 2013-2018 by 0.8 percent annually. By assigning this additional labor supply to Poland's economic growth accounts, the researchers found that the contribution of Ukrainian workers to our economy (previously not included) was around 0.5 percentage points per year or around 13 percent of Poland's GDP growth in 2013-2018.