Dividend Yield of a stock measures the Cash Dividend that is paid out to its shareholders per year relative to every rupee invested in its equity. It is expressed as a percentage.
Dividend Yield = Annual Dividend per share / Current market price per share
Dividend Payout Ratio measures the percentage of net earnings that is paid out to shareholders in the form of dividends.
Dividend Payout Ratio = Dividend per share/Earnings per share
Retention ratio that is, the percentage of net earnings that is not distributed to shareholders as dividends is the inverse of Dividend Payout Ratio.
Retention Ratio = 1 - Dividend Payout Ratio
= 1 - Dividend per share/Earnings per share