We have found a mystery in an Excel-formula : the result displayed on screen is DIFFERENT from the formula result displayed in the formula box, when the formula is edited. The result on screen is FALSE, while the formula result in the "Edit formula" is CORRECT !
These are the formulas and values entered in the cells :
The first formula "=PRODUCT(B3:E3)" is OK. The second formula "=PRODUCT(1+B2:E2)" gives a result on screen which is equal to "=PRODUCT(1+B2)" but when clicking on the "=" (Edit Formula) in the formula toolbar, the displayed formula result is OK, equal to (1+4%) *(1+3%) * (1+5%) *(1+6%) = 1,192246.
This problem doesn't occur when the SUMPRODUCT-function is used on the same data.