Who created the concept of "present value"? I cannot find anything on this online. The wikipedia article is purely technical, except by a mention that such system was used in England in early 16th century.

Do you know who was the first to come up with this idea and technique?
It has been argued that the concept of present value was implicit in Liber Abaci (1202) by Leonardo of Pisa (also known as Fibonacci).  This paper by Goetzmann makes this claim in its abstract and introduction, and presents (pp 26-7) an example from Liber Abaci of what appears to be present value analysis.