n. The time a person has to enjoy life versus the time a person spends accumulating material goods.
2001
As families become more affluent, sometimes they begin to suffer from what has come to be called "affluenza": They focus their lives around accumulating more and more stuff that they have less and less time to enjoy; their "joy-to-stuff ratio" gets out of balance.
1995 (earliest)
You're not really spending money when you spend money, Joe and Vicki say. You're spending the life energy you put into earning that money. You only have so much life energy. What do you want to use it for? Commuting? Shopping sprees? Going for walks? Playing with your children? Serving your community? Taking that question seriously does wonders for one's joy-to-stuff ratio, decreasing stuff, increasing joy.
To the definition of this phrase, I should add that time spent accumulating goods includes time spent at a hateful job that a person sticks with because they need the income to purchase fancy clothes, expensive cars, and other nonessential stuff. (For the exam, you should note that the word stuff has been a paid-in-full member of the language since at least 1330, but the colloquial "collection of unspecified things" sense of the word has only been around since the 1920s.) From now on, when people ask me why I do Word Spy (and what they always really mean is why do I do it for free), I'm going to tell them that it adds a considerable amount to my "joy" numerator.