Buyers in today’s market can expect to pay about 17 percent of their gross monthly income on their mortgage. The average, since 1975, has been 25 percent and at times, such as the early 1980s, mortgage payments were as much as 45 percent of gross income. calculated housing affordability using data dating back to 1975. Based on median household income, median home value, the average 30-year fixed-rate mortgage, and an assumed 20 percent down payment, their research determined that homes are more affordable now than they’ve been at any point in the past 35 years. More here.