Weighing a contract offer against waiting after 15 years as a data-entry clerk

I got a contract offer for 15 months as a data-entry clerk and I am unsure whether to accept. I have been trying to stay organised about it. The contract could extend. Did a contract become permanent?

Thanks for writing this out. I went through something close to it last year, and it got easier once I kept a simple log of every call and form.