"Automated process 'x', saving company $10,000 per year" is meaningless without knowing whether $10,000 is a significant figure or a drop in the bucket. Also, if they paid you $100,000 to automate it, it'll be 10 years before they see a return on that investment, and by then your code/process/system may have been rewritten.

I'd much rather see percentages, and if they can want to clarify with hard dollar amounts, so much the better.