Basically, In summary the idea of 11% of the Spanish population seems right to you, so you believe the evidence and seem indignant and think me stupid that I don't. It seems wrong to me so I disbelieve it. C'est la vie.
It would help if you knew what you were disbelieving.
It's not 11% of the population, it's 11% of households. The population of Spain is 46m and there are 16m households.