States with crossover at 55 are undesirable for retirement (bad climate). States with crossover at 75 are popular retirement destinations. Starting at 55, baby boomers from New Jersey cash out their equity and move to Florida. Starting at 75, baby boomers from Florida sell their houses and move to retirement homes (or die).
The only exception is California which is nice climate-wise but so expensive that few people can afford to retire there.
Fortunately now we have a lot of affordable inventory in parts of the country with dry warm climate – Riverside, San Bernardino, San Joaquin counties.