[j2bax]

I've found that using past data is very helpful. Look at your past projects, compare your initial estimates to the actual outcome when the project was finished. After a dozen or so projects, you should be able to formulate a percentage buffer to help you get closer on future estimates. Continually make this assessment and eventually you will find that you are getting much closer to accurate budgets/timelines.

[moron4hire]

If I have any past projects that are good indications of my current work, it means I'm stuck doing the same things over and over again.

[j2bax]

I don't think building on your past successes and mistakes and using the raw data to improve your future endeavors should be considered stuck doing the same thing over and over again. Surely there will be some overlap of knowledge with each project you take on... Or do you only go for projects with completely foreign problems to anything you've ever worked on before?

[moron4hire]

I've never worked on two projects that did the same things other than "let people login", which I usually have settled in the project before anyone even starts talking about estimates. I've never worked on two projects with even the same reporting frameworks. Hell, only a few of them have even been in the same application framework.

I've never worked on two projects with the same team. There's as much learning about how to work with new, particular individuals as there is to learn about what the client needs.

Insomuch that anything has remained constant, it was pretty much just the underlying programming language, but even that has changed dramatically over the years, as well as opinions on the best way in which one should write it. Certainly my understanding of it has drastically improved.

And I'm not exactly sure what you're suggesting by "raw data". What sort of data? Collected and stored how? Reported on in what ways?