I need to find the Internal Rate of Return (IRR) of irregular payments. I would prefer to find all the solutions for a given series of payments (i.e. (update: real) zeros of the corresponding polynomial) but it would be sufficient to find only the largest and smallest positive real zeros.

I have seen Finance::Math::IRR, but this only finds one solution. Other modules I have found that are specific to IRR or NPV only deal with regular schedules of payments.

It may be that I will have to turn to modules for solving polynomials in general, but I am not familiar with the mathematics, numerical methods or available modules. I would be interested in solutions that are effective for polynomials with orders up to a few hundred (schedules of monthly payments spanning one to 25 years).

Any pointers or suggestions would be much appreciated.

In reply to Internal Rate of Return by ig

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