Unity UI How to create a slider with the default middle value as non-zero?

Hello,

I currently have created a slider with values from: -100 to 100, where the initial value starts at 0.
I want to have the slider start at a non-zero value, such as 30 and be able to range from 20 to 40.
The reason I want this is that I am showing the numerical value of the sliders in a text component.

I'm quite new to Unity (as in I started today) and I've tried searching up some stuff but I just couldn't find anything about this.

Thank you!