If you are not already depressed about the state of public education in Catalunya, read this report by the Fundatio Jaume Bofill.
Catalunya spends 2% of its GDP basis on pre-university education vs an average of 3% for Spain.
Does this affect outcomes? A simple linear regression suggests the answer might be yes.
And yes, that is Catalunya sitting down there at a proud 61% graduation rate in the public system, the worst in Spain.