How to calculate net change
You can calculate net change by subtracting the current day’s closing price for an asset from the closing price of the previous day. For example, if company ABC’s stock closes at CHF 125 per share today – after closing at CHF 130 the previous day – then there has been a negative net change of CHF 5 and you might decide to go short.
If, however, the price had increased to CHF 135, up from CHF 130 yesterday, then there has been a positive net change of CHF 5. In this case, you might decide to take a long position.