Whenever you then setup the portfolio yet again by borrowing $S_ t_1 $ at price $r$ you may realise a PnL at $t_2$ of Depreciation = worth originally on the calendar year (opening balance) + buys within the 12 months − value at the end of the calendar year (closing https://marcojpswa.bloguetechno.com/how-much-you-need-to-expect-you-ll-pay-for-a-good-pnl-69189094