RE: Math question - Calculating new average SP20 Sep 2021 20:54
@MarquessR
The simplest way to do this is just to add all your initial investments (in £s) together, including those purchased in the RI, and divide by your total number of shares (again including the new shares purchased in the RI). So just like working out a normal average price really.
For example suppose you have 4700 shares that were bought at an average price of £10 so you have invested £47,000 previously.
The RI meant you could buy 3100 more shares at £4.10, so costing £12,710
So the total you have now invested is £59,710 and your number of shares is now 7800.
So your average price is simply 59710/7800 i.e £7.66.
This is the key figure as it is what you need to get back to in order to break-even (ignoring costs). You are no longer aiming for £10 but only £7.66. Accordingly any previous target sell prices you had in mind also have to be similarly reduced.
Hope this makes sense and helps.