Any time you then set up the portfolio again by borrowing $S_ t_1 $ at level $r$ you may realise a PnL at $t_2$ of $begingroup$ Assuming you are Doing work for the financial institution, you'll find three various P&Ls according to the operate/ utilization: PNL have been set to https://www.youtube.com/watch?v=qMmsQ4kKgY4