Some years ago, we were researching innovative ways to create tools which could help people figure out a long savings plan in order to provide a sustainable income in retirement. My company has a wealth of software and research assets which we were planning to deploy but I figured it'd be a good idea to think about the number crunching from first principles; so I set about creating a rough model in Excel. After an evening's work at home, I'd created this. It's by no means sophisticated and, unlike many of the solutions which we've subsequently created at work, is purely deterministic rather than employing a robust stochastic method. If you find it useful, feel free to use it for non-commercial purposes (under an Open Source licence).
Please note just a couple of things:
- It's not finished! It served my purpose of getting my head around the problem in terms of the mathematical background and I left it at that.
- You'll notice it's geared around the UK tax regime.
You can download it here - you do so and use it at your own risk!