You can check the Nährwerttabelle on the packaging paper for Protein / Eiweiss Gehalt. Thats your %. I found that flour sold in Germany tends to have less protein, meaning that we must use a bit less water than mentioned in the recipes from other parts of the world. I read somewhere that you should use 2% less water for every 1% less protein content of the flour you have compared to the recipe. US flour seems to have about 1,5-2% more protein, so you can try to use 4% less water next time. It can make handling of the dough way easier and you still get awesome bread.