One of the challenges I currently have is with systems I have created. Some I have 3 months of data, some six months. I have some that I have more than 12 months of data and I am quite comfortable trading those. So after 12 months of data I am more comfortable but it is no guarantee that they will continue to work. What you include in those systems will determine whether they will work or not. I include rules which I think will work long term and not too restrictive. My question is how much data do you need? Once you start placing bets then the system falls over and this can destroy your confidence. I am not working at the moment so I cannot lose money long term so I can't afford to take risks on untried systems. But then again seeing a system constantly win without being on also is hard to swallow. I had one of my systems which I only have 2 months of data get 3 winners last night. So what is the right balance. Interested to get some viewpoints from others.