Best way to show old value vs new value in a list of items

I am working on a screen with a list of diagnostics data on the right side of the screen (1/3 of the width).

The customer requested to be able to see the current and previous values close together so that they can determine how the system got into its current state.

What is the best way to show a label, current value, and previous value close together in a small amount of space on the screen?

For example, I could use a table with three columns, but some of these values might be long and I don't think that would look the best.

Here is an example mock-up:

old value / new value example

I purposely truncated the program name to show the issue of space.

Would it perhaps be better to stack old values and new values vertically in one cell? The customer is specific that they want to see all of the old and new values at once.