I've been trying to figure out how to calculate what percent of the way to a target one number is.

Eg:

Code:

Starting Value Target Value Current Value Percent Complete
100 300 100 0
100 300 150 25
100 300 200 50
100 300 250 75
100 300 300 100

Or:

Code:

Starting Value Target Value Current Value Percent Complete
70 140 70 0
70 140 105 50
70 140 140 1

The three left hand columns I have, the right hand I need to calculate, but after spending ages failing in Excel, the answer eludes me. If I get it to work with one value, it doesn't work with another. For the lower table, seems to work, but the upper table, seems to work. There must be a universal equation.