Lately my sports betting strategy has encountered a bad drawdown and has lost more than 20% of the profits. While it still remains profitable, that drawdown has aroused some concerns and needs to be re-evaluated. Let's see some interesting statistics:

• Flat betting plan applied: EUR500 fixed stake
• Total turnover: EUR2,587,000
  
• ROI (yield): 2.98%
• Total Bets: 5,174
  
• Database's games: 8,650
  

The sample is quite large for trustworthy conclusions and here are some more useful calculations (read how to do them yourself here):

• Average (mean): 15.69
• Standard Deviation: 533.44
• Confidence (95% significance level): 14.92

Things do look a bit rough at the moment but...

We have defined our bankroll and staking plan we are going to apply and we may now calculate how much winnings we should expect and when we will make our first withdrawal. Because, after all, if we are not going to spend our hard earned money, what is the point to build our Betting System in the first place?

Yes, of course we would be proud of our achievement and we would gain extreme self-confidence, but it is the biggest satisfaction to know that you bought some goods with the profits of betting!

So, let's see if the bank's safe will be big enough to keep all our profits inside... 

We have now arrived to the point we  are confident with our probability calculations  and understand value betting , and we want with no further delay to submit our bets and start making money. However, if we don't bet according to a staking plan and not having defined any bankroll for our system, we will be lucky not to end up bankrupt. But what are the staking plans we can choose from, which one is most appropriate for our system and how can we calculate the bankroll we are going to need?

All these are found in this article being  the fourth one on the Series about how to build your own Betting System...

Usually, inputing data, variables and stats into an excel spreadsheet is dull and when it's done on a daily basis it can get frustrating. Now, the clever part of building a betting system is making proper use of those numbers in order to calculate a probability percentage as close as possible to the real probability of an event. How this is done depends only on the bettor's knowledge, skill and method. Here is how you can do it...

Having already discussed about selecting a sport to bet on in the tutorial series on how to build your own Betting System, it's time to deal with the input variables of the system we are going to develop. Now, don't panic, by saying "input variables" doesn't mean we plan on building a nuclear reactor! We will have some data entered in our system in order to make our calculations. That data can be anything that we found useful and in referance to the sport we have already selected. Let's see some examples...