I wont be able to get to computer for a few days but wanted to share this weeks progress so far.
I adjusted the stake, on Thursday evening, back to a flat £2 after thinking that the current poor performance was related to the last staking plan change. As can be seen on the chart there was an immediate change in trend, the losses were less significant. I still think that the flat £2 (or any set number) is a bit crude and there may be a better way of staking but I need to do some proper testing and checking before implementing. For example around the whole numbers, ie at 2.00, 3.00, etc, the change in step per tick from say 0.02 to 0.05 can mean a disproportionate loss at 3 ticks than profit from 1 tick.