How much can I realistically write in one hour?

I'd like to know from you how long it takes you to write a single page.

Once, I made a special effort to ask all the prolific publishers in my university how long they take to write a page.

Without hearing each other's answers, they all said - About an hour - provided I have all the material and have written something similar before.

An hour per page - for experienced writers, for confident writers.  On subjects they know well and have written about before.  On material which has no gaps.

Realistically, a novice writer will take a hour to write a paragraph with a few stops and starts.  And that's provided all the facts and figures are in front of them.  Provided they have some idea of where they are going.

That hours is for ordering and phrasing.  An hour.