# Yield (ROI = Return Of Investment) formula question

1. Aug 20, 2007

### rivica

[SOLVED] Yield (ROI = Return Of Investment) formula question

The Calculation of simple yield:

The Return*
(Winnings)
__________ X 100= ROI (%)

Investment*
(Stakes)

so for example: I have 1000 bets with odds 2,00
500 of them are winning and 500 losing. So i am on 0 and my ROI is zero

Would like to get right odds to have 15% yield,
How to calculate on what odds should i be to have ROI 15% ?
Because odds are not always 2,00 - they are different but i gave 2,00 as example...

So, i know what are odds to have 0% yield, but would like to get with some formula odds to have 15% yield (ROI)!?

Thanks very much for help!
Ivica

2. Aug 20, 2007

### CRGreathouse

Let p = 1/odds be the probability of success, and R = 2 be the amount you win on a success (as a multiple of the amount you put down). Suppose you play n games, where n is large (in your case n = 1000, but it doesn't really matter).

Expected winnings are npR, and expected cost is n. ROI is (npR - n)/n = pR - 1.

If you want ROI to be 0.15, just solve pR - 1 = 0.15. If R is fixed at 2.00, solve 2p - 1 = 0.15.

3. Aug 20, 2007

### rivica

Thanks for answering, but I'm not that good in maths, so could you please give me calculation on some example?
Let's say i have odds of 1,50 (so probability is 66,66%) so to receive odds which would provide us ROI of 15%
I'm trying to do it into excel formula, but don't understand all what you write...
so please if you could calculate it step by step... tnx

4. Aug 20, 2007

### EnumaElish

In Excel:
1. Enter R to cell A1
2. Enter ROI to cell B1
3. To cell C1, enter formula "= A1/(1 + B1)"