Americans are borrowing more, renting more rather than owning, eating in class="mandelbrot_refrag"> restaurants more and saving less, leading inevitably to questions of sustainability. That’s true both for Americans and for the corporations whose profits they create. What’s more, the kind of financing backing all this indicates that a goodly bit of the balance sheet straining activity is concentrated lower down the income and wealth scale. Juxtapose this with vertiginous rates of corporate profitability (and intriguing hints that a top may have been hit) and you have the making of some serious upcoming tests for the class="mandelbrot_refrag"> economy and stock market. true First, let’s look at Americans and their cars. A record 27.9 percent of all new car sales so far this year were leases, according to Edmunds.com, while those who did decide to buy did so with record-long loan terms of 66 months on average. Interestingly, leasing, which