On average across OECD countries, as many as 51 % of foreign-born students with immigrant parents failed to reach baseline academic proficiency …

„Results from PISA 2015 reveal that on average across OECD countries, as many as 51 % of foreign-born students with immigrant parents failed to reach baseline academic proficiency in mathematics, reading and science, compared to only 28 % of students without an immigrant background.“
OECD (Hrsg.), Changing the Odds for Vulnerable Children (2019), S. 37.