You can think of the ideal resume entry as a little story: here's the settings, here's why I did what I did, here's what I did, here's the outcome.
The goal is to have that story resonate with the reader: "Oh djellybeans went and did this thing in a new product, and we're a new product and we have similar problems, maybe they can do that for us!"
Accomplishments are the last bit of the story, and ideally you have all of them.
Now, savings lots of money is great, and if someone measured it you can include it. Consider measuring this stuff yourself, even if management doesn't. But the real goal is to explain why this matters, why it's useful, why the reader should care, in a way that will match their concerns.
Here's an example from my resume, where I wrote a new config format for ops team at an old employer. Here how's I might have all four of the elements of the story:
1. Setting: The ops team managed hundreds of servers with similar but not identical configuration.
2. Motivation: Noticing that this made configuring servers difficult,
3. What I did: I implemented a prototype-based configuration system, where one system's configuration could inherit that of another.
4. Accomplishment/outcome: This allowed them to significantly simplify their configuration, reducing opportunities for errors and unwanted divergence.
Notice that item #4, accomplishments, has no numbers. But it still explains why the reader should care, and the things I might be able to help them with.