How to find several slopes

Hello...imagine this:

N=[1;2;3;4;5;6;7;8;9]
B=[9;8;7;6;5;4;3;2;1]

I need to find

(change in N)/(Change in B) % for each instance.

What's the code for that please

Thanks

[darova]

Attention!

Answer 1

[madhan ravi]

help diff % calculates the change between each instances

[DARLINGTON ETAJE]

Thank You