ΔIRR, what would that be? Anyways, -IRR and a +NPV means the project is inconsistent. what is this ΔIRR????
You'll want to use NPV (over IRR) for the investment decision-making criteria for projects with equal lives.
I am not familiar with "ΔIRR"...the change in IRR?...so I can't help you there, sorry. But, if it represents some way to measure "cost", as I infer from the question, a 'negative' cost is a positive so it would make sense to order highest to lowest cost with the largest negative amount being the last on the list. (I'm going nuts trying to find info on ΔIRR - but no luck!)
I'm having a hard time understanding when to use IRR or NPV to determine which alternative is better.
Suppose you have 5 machines to choose from (equal lives) and all have a IRR >= MARR. This would mean that they're all good investments, but we need to do ΔIRR in order of High cost and Low cost. My problem is that once I recalculate ΔIRR, I get a negative IRR. What happens in this case? How do I know which machine to pick?
