Well, in case you didn't know, each countries have different salaries, labour laws, holiday per year, social welfare, etc ...
A Iirish will get 2-3 times higher salary than a Portuguese.
A French will get much more holiday than a Belgian.
So basically, this 'survey' compares irrelevant economy system.
How can you compare someone who gets 950€ per month to someone who gets 2300€ and make an average of it. It's not rocket science.
As for Germany, you can make your own deduction.