Add only changed numbers to a running list

Question

I am trying to log values for a meter at one minute intervals. In lieu of entering the full value each time, I want to be able to enter just the numbers that are different: as opposed to entering the difference of the values or the entire number.

I have a rather cumbersome formula for doing this and it's good for new digits greater than zero but less than ten, after that, it just adds the number to the total.

If I could just enter the new digits, that would be ideal, whether they be .65, 1.25, 35.95, or 501.69 etc.

Thank you!

Answer 1

I attacked it from the other direction and it now does what I want with a few less backflips.

It still removes the decimal so a trailing zero doesn't get lost in LEN().

1. Whatever the number of digits that are in the new number, it replaces that number of digits out of the original number with zeroes.
2. It adds the new number to the modified number.
3. It divides by 100 to get the decimal back.

I have no doubt there is a much more elegant way of doing this.

Thank you!