Market Movements.

No.

This is primarily by virtue of the iceberg factor.

Is that global warming at work ?

Can be done in excel for totalisator type betting with some degree of accuracy.

For fixed price betting I don't think it would be of any value.

In excel you enter all the variables, the current dividend for each selection, the total pool, the tote take, and with some
basic calculations it comes up with how many units are on each selection. Adding a further bet adds to the pool and then recalculates
all the dividends taking into account the tax take of the tote and the increased amount of units placed on the selection.

Thanks very much Compound Magic.
Found this most helpful.

There is no method for BF.

Because the essence of a market is that price changes bring in more buyers/sellers (backers/layers).

And I'd add that serious traders will try not to distort (move) prices. If I could put as much money as I like into markets without affecting prices, I would be a very rich man.