Yep, I looked it up: about 90% of all employees in Belgium legally benefit from a 13th month's payment. Only downside is that there are some 50% taxes on that payment...
My former employer also payed us a '14th month': an annual share in the company's profits... That is, until our company was taken over by an American company; they sacked 4000 employees in Europe and kept the profits...

We do not see things as they are. ǝɹɐ ǝʍ sɐ sƃuıɥʇ ǝǝs ǝʍ