How are the salaries made comparable?
Every salary is in one unit: gross per month for a 40 hour week, excluding holiday allowance. An annual figure is turned back into a monthly one without the allowance, an hourly rate is converted at 40 hours times 52 weeks divided by 12 months, and a band for fewer hours is scaled to 40. The median across the whole database is €5,625 right now. Each band says whether it was published, taken from a closed record, or estimated.