Enter the current price to get the yield, and the purchase price for the yield on cost. Leave at zero to skip them.
The net figure deducts the 28% Portuguese withholding on dividends paid to residents (Art. 71/72 CIRS). You can opt for aggregation at the progressive rates instead; foreign dividends may carry a withholding at source with a tax credit.
Dividend yield measures the dividend against the current share price; yield on cost measures it against the price you paid. When the share has risen since you bought it, yield on cost is higher than the dividend yield.
Educational estimate, not financial or tax advice. The dividend per share is not guaranteed and can be cut; the net figure assumes the 28% withholding for residents.