# 04/07/2019

**1. What is the formula for the volume of money traded at a certain price?**

Use the `traded_{price}`

variable where {price} is the price (it can be another variable) at which the money is traded. For example, to check how much money has been matched at the current back price of a selection, use this formula:

`traded_back_price`

To find out how much has been traded at a certain price or higher, use `tradedh_{price}`

. For example, to get the amount of money traded at any price equal or higher than 5.0. Similarly, to get the amount matched at a certain price or lower, use `tradedl_{price}`

.

**2. I want to back on a set of football selections to an equal profit (Dutching). How do I know if the Dutching is possible, i.e. will not lead to a loss?**

I have put together all the Dutching formulae in these articles:

Single-Market Dutching Formulae

Cross-Market Dutching Formulae

In the general case, for back Dutching, if you add up 100 divided by the price of each selection, the sum must be less than 100 in order for the Dutching to be profitable. In other words, the book% must be < 100%.

If you introduce the exchange commission, the calculation becomes slightly more complicated. But we have prepared a spreadsheet that will help you with the numbers – just key in the prices of your selections and check the P/L column.

Download the Dutching calculation spreadsheet.

**3. In Market Locator, how do I search for markets from my own list (e.g. in a text file)?**

You can make a list of markets you want to search. You can write only a part of the market name, just make sure that the names of venues, teams, players, etc. are exactly as on BetFair. Also, enclose each entry in double quotes. Here is an example of a valid list of market names:

`"Aoyama/Krunic"`

"Mertens v Q Wang"

"23:16 Monm"

"FC Inter - Lahti"

"00:00 Monm"

Add a condition to your Market Locator search template to look for markets mentioned in the text file.

**4. I want to bet on the favourite, but only if the fourth favourite’s price is >= 10. How do I specify this in a condition?**

You can address selections by their rank using the `r_{number}_`

prefix. Specifically, `r_1_`

stands for the first favourite (the selection with the lowest non-zero price), `r_2_`

for the second favourite and so on.

So the answer to the question above is:

`Selection’s Trigger Expression r_4_back_price is equal or greater than 10`

Alternatively, you can address selections by their index (position) in the list, as opposed to their rank. The order of the selections as they appear on BetFair is rarely changed after the market has been made available, and in some markets (such as all football markets) this order never changes. So you can rely on the fact that all Over x.5 selections will always be in the second place, and all “The Draw” selections will have the index of 3.

You can address selections by their index using the `s_{number}_`

prefix, e.g. `s_1_sel_name`

for the name of the first selection.

**5****. If I include a runner multiple times in an import file, is it possible for the bot to place bets as many times as the selection appears?**

Yes, but with a little tweak. Edit the list of selections in such a way, that instead of appearing multiple times in the list, the selection has a number next to its name (separated from the name with a Tab character). The number must denote the number of bets that must be placed on this selection.

Example:

`"Rusty Boy" 1`

"Bigfoot" 3

This means 3 bets must be placed on Bigfoot and 1 bet on Rusty Boy.

Then in the triggers, set the betting trigger to repeat "no more often than xxx secs" and add the condition like the ones below.