The price-to-rent ratio is calculated by dividing the median home price by the median yearly rent and the formula for the price-to-rent ratio is:. Partner Links. The housing affordability index lays out whether an average family can afford the property based on home prices and income levels. Home Ownership. Before the housing bubble and subsequent crisis around , the national price-to-rent ratio hovered around The following table has price-to-rent ratios for each of the five New York boroughs.