I've played a bit with that and it is clear that the relation is linear, so calculating the total time is a simple multiplication between the exact distance (I used two digits after comma) and the per square value.
I could not find though what is the relation between the per square value to the base level (also again using the base level with 2 digits after comma).
I've tried in the same world (to remove that variable) to look at multiple bases with different levels and the one space jump (exactly 1.00) and could not figure a relation.