The traditional view of housing affordability is 30 percent of income. Neighborhoods are considered ''affordable'' to the typical household. However, we recognized that this benchmark failed to account for transportation costs, which are typically a household's second-largest located in outlying areas that require residents to rely on cars to pass along hidden costs, often making such '' affordable'' housing unaffordable. Transportation costs also vary dramatically within and across regions. Hosing located in outlying areas that require residents to rely on cars passes along hidden costs, often making such ''affordable'' housing unaffordable. We believe now is the time to redefine ''affordability'' and to set a new target - one that is realistic and one that is likely to have a more tangible impact on affordability and access, particularly among the last billions to connect. Determining a new target requires consideration of several factors. These include the challenges associated with inequality, focusing on those at the base of the pyramid, and considering those countries still struggling to reach the current 5% target so that none are left behind. It also must consider the need for sustainable business models, including how best to incentivize the private sector so they extend access and improve service provision in unserved and underserved areas where low-income communities reside.

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