N = Portfolio Control divided by Number of Shares
For the next sell price divide N by 1 minus safe minus minimum trade % i.e. if safe = 10%, minimum trade size = 5% then 1 - 0.1 - 0.05 = 0.85 (so N / 0.85)
For next buy price divide N by 1 + safe + minimum trade % i.e. if safe = 10% minimum trade size = 5% then 1 + 0.1 + 0.05 = 1.15 (so N / 1.15)
Yep, those are the figures alright. I added in Portfolio control and stock holdings so it is a match to the web site calculator, but I haven't figured out the best way to do the value of the stock instead of the price per share.
You've lost me somewhat Allen. You only need Portfolio Control, # Shares and cash reserve (and safe, minimum trade size, vealie-at if you use different values for different holdings). With PC and # Shares you can pre-calculate the next buy/sell prices and record those figures and you only need to review when the share price reaches/breaches one of those price levels. Then its a calculation to see how much stock to sell/buy, check whether you're above/below a Vealie level etc and either buy/sell or adjust PC for a Vealie accordingly (sell trade indicated but already too much cash reserve).
Recording weekly/monthly/quarterly prices is only useful if you want to create charts, otherwise its just clutter (that can usually be downloaded if you have the need). Otherwise just carry a piece of paper around in your wallet with a single line for each stock/fund (AIM) containing stock name, PC, #Shares, cash $, next buy price, next sell price (plus safe, min trade size, vealie at ..etc if you don't consistently use the same settings for all your AIM's).
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