The $80-20$ rule, which is often used by industrial marketers, states that $q,$

only $80$ percent of consumer demand can be fulfilled, while $20$ percent remains unfulfilled

$20$ percent of buyers account for $80$ percent of sales volume

$80$ percent of company expenditure is on marketing and only $20$ percent is on production

only $20$ percent of customers return $80$ percent of the products they purchase