String Formula returning to much decimals

String Formula returning to much decimals

Hi all, 

Maybe a counter intuitive topic, but I'm looking to have a formula field turning numeric values into a string, because i would like to have a blank field instead of a '0' if the value is equal to 0.

My formula looks like this : 

If(IsEmpty(${Articles en devis.Remise (%)}),'',Concat('€ ',Tostring(Round((${Articles en devis.Tarif}*${Articles en devis.Quantité})*(${Articles en devis.Remise (%)}/100))),2))

Syntax is okay, only issue I have is that sometimes it would display me values like : € 60.600000000000

I would think using the Round function would help me but apparently it doesn't change anything

Why do I have so many decimals, how to get rid of them ? 

Thank you for your help