Udemy's Marketplace insights inaccurate??!

[EricRS976]

I am not a math teacher but, when I look at the insights I see two numbers. I see a median monthly revenue and I see the Top monthly revenue - The numbers no matter what subject I choose to search are always pretty far from each other. Obviously, some subjects are further than others are.

However, if you search the insights you get something that looks like this. I am not showing anything someone with an account can access. 

I am not that much into math, but for the median to be "25" USD, then someone would need to be earning negative -113,550 USD at least or something in that ball park. Does "median" for Udemy mean something different than what it is used in math or am I just not understanding something?  Any help would be appreciated.

[VirajShetty265]

Median just means that half the instructors earn greater than that per month for that topic. If you arrange the instructors earnings in an increasing order, the one in the middle is the median. Also, note that these numbers also include Udemy's share (not just instructor).  It's a little misleading. 

Top monthly revenue

Average monthly revenue per course (includes both Udemy's and instructors' share) of the top courses over the last 3 months (not including the current month).