How to work out ROI ?

[oscar123]

Sorry about this,

And I have tried google, but I cant get it to work.

How do I get excel to add up the numbers in column J ?

Ive tried clicking on the cell underneath, then typing =SUM(J3:J1382)

But it just comes out as 0.

Anybody help by pointing out the obvious here?!

[oscar123]

Its ok, ive got there eventually!

I needed to click the little exclamation mark and convert the text to a number!

Thanks all.

[tilopa44]

I don't believe this statistic is very useful for traders (by which I mean anyone who both backs and lays in a market) as it's not a reflection of the risk you are taking. For traditional gamblers, who are only backing, they can work out what they are making per unit invested by looking at the ROI. As a trader you cannot do this.

For instance, someone who has backed at 1.01 for £10,000 has added £10,000 to what Betfair call 'bet volume' (turnover), but someone who lays at 101 risking the same amount has added £100. They are essentially making the same bet with the same risk/reward.

This bias also exists in Betfair's own amount matched figures used to show how much has been matched per market.

If you take the inverse of your lay bets to work out what odds you would have backed at (even if no such back bet exists), and add this to the total stakes of your back bets, you get a more accurate reflection of the amount risked. However this still doesn't take into account trading. For instance, with a bank of £2,000, you could 'risk' £50,000 on a market by trading.

NET risk (your maximum liability at any point in a market) is much more difficult to work out after the fact. Should you factor in unmatched bets? Does anyone use a macro or something else to work this out from the account statement?

The most important metric for me is percentage growth of my bank per year as I aim to compound profits.

Having said that, this bias might not matter that much for some of you. As I place a lot of bets at the extreme side of the odds, my figures get heavily skewed.

[CaerMyrddin]

Great post tilopa44.

I agree with you that the metrics to this problem is difficult to set....

And I'm also using the % growth but must admit it's a poor metric, as it doesn't take into account the amount of money you would need to put your trades in.

In a certain way this problem is linked with the one that has been discussed on another thread (can't find the link) where a BA user suggested that we were able to set BA to calculate stakes so that you had the same profit/loss for one tick gain/loss on a given interval. The problem is that you are not buying units of something, but taking risk and covering it with money.

Any suggestions to make this conversion?