> 3) how many workers there are per retiree Rather, total production of workers per retiree. More kids from economically unproductive population segments, and

> 3) how many workers there are per retiree Rather, total production of workers per retiree. More kids from economically unproductive population segments, and more immigrants to unproductive population segments don't help future retirees. It seems likely to me that political change is the mostly likely result from a future pension crisis: another government expansion of responsibilities for old age income and health care.