Yahoo Finance vs Google Finance return difference

I've found that Google Finance and Yahoo Finance have different formula for calculating stock return over a period.

Yahoo Finance uses the closing price of the periods involved and Google Finance uses the opening price of the period start and closing price of period end.

I think Google engineers are smarter than Yahoo engineers. But I'm very confused why Google chose this.

As an example, in Yahoo Finance NVDA stock shows up as 2.68% return for 5-days (i.e. this just concluded trading week), versus 3.98% in Google Finance. $LY (ADR) (YAHOY.US)$ $Alphabet-C (GOOG.US)$