> a maddening lack of a definition for "disposable income". Not really. The article goes into pretty good depth about its logic comparing them in pre-tax incom

> a maddening lack of a definition for "disposable income". Not really. The article goes into pretty good depth about its logic comparing them in pre-tax income (gross income) and after-tax (what it is calling "disposable income") across various countries. http://www.pewglobal.org/2017/04/24/western-europe-middle-class-appendix-c/ http://www.pewglobal.org/2017/04/24/western-europe-middle-cl... Thus, when gross income is used to define income tiers, the result is that higher shares of adults are estimated to be lower income or upper income, and smaller shares of adults are estimated to be middle income. The chart here is telling, too: http://www.pewglobal.org/2017/04/24/western-europe-middle-class-appendix-e/ http://www.pewglobal.org/2017/04/24/western-europe-middle-cl...