I'm trying to get better Caribbean regional ability estimates. Bonaire, Sint Eustatius, and Saba are still administrated by the Netherlands, so national test data should be available. I came across the following:

Figuur 2.4.1b Gemiddelde vaardigheidsscores in "ONDERWIJSVERBETERING IN CARIBISCH NEDERLAND".

Can anyone make sense of this? What are the typical CITO-rekenen-wiskunde standard deviations?