People don't have statistics to play gamble and that is why some of the gambling enthusiasm do experience (shege in gambling... meaning much loses in a gambling) so it's good for gamblers to know a specific amount that should go out in their wallet weekly or monthly..
In gambling, there are two types of people one who plays just to spend some time and for fun and the 2nd one does gambling to make money. The first one is very because they spend money to have some fun they do not care about the loss or profit but the second one play every day to make money and they do not tolerate the loss as they do a high bit and when they lose they are very disturbed. So for those people, I think the chart is necessary every day week, or month how much they need to spend on gambling how much loss they can afford, and how much profit they need to make the effort. If they set these few things they will not fall in loss or loans and will get their profit easily.