New answers tagged book
To get a rough estimation, have a look on how long it took a few of your favourite series to be written (so you get an idea of your favourite style/genre of writing). Once you've done that, get the average.
That depends (a) on your level of professionalism and (b) on the necessary research. Some topics need a lot of preparation, and some authors spend months or years to research into the background of their writing. Some authors have a good idea, plan well and write printable prose, so they finish a thousand pages in a few weeks. Others need to restructure, ...
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