Added Number in between

[Side.Order]

hey Excel experts, got something for you i can not simply figure this out, and its kind of annoying so here it goes,

i got a level at "35" and you have to hit 9,989,875, ok...
at level 34 you need 9,427,180, ok...
that's um 562,695 for the gap

i need a way to find out how to get that gap added up but hears the thing i only have that one column to add it up not 2. im going a bit hard on you just a little; take a look, i know i cant explain it very good. if you can help it will most appreciated

Comfuzzled.xlsx