I created a new pie and invested £500 (£498 after FX fees, etc.) The next day, the pie was worth £502, but the calculated return was -£9.88 (-1.94%). This makes it look like the pie has lost value when it is worth more than what I transferred into it.
It appears that one of the investments is with a company that I have in another pie, and it has averaged the negative return from the other pie across both.
I understand that T212 uses an average share price and generally I like that, but it would be nice to be able to track the performance of an individual pie without the influence of investments outside of the pie.
