Translate yourself this salary ranking:
You can see there min, max, avg salaries from Hays recruitment company, so what they describe there as Min. is actually maximum in smaller companies or out of the biggest cities. In other words there is written:
SAP Consultant min: 9 000 max: 20 000 median: 13 000
You can understand this, that 13 000 is an average salary in top international (cause these pay usually more) companies in Poland.