A Hemline Index, Updated By TAMAR LEWIN More suicides? Fewer male births? Less back pain? More laxative sales? Data points litter the landscape as economists, sociologists, psychologists and marketers examine the societal changes, big and small, trivial and traumatic, that accompany a bad economy. And with this particular version of a troubled economy — a stock market that goes into convulsions at 3 p.m., a looming global recession, a $700 billion bailout plan that may or may not work, and a jittery public wondering what is coming next — changes should flow as freely as profits in good times. It’s...