Reasonable models can be useful to quantitative analysis of the structures and define the timing and active ratio.

合理的模型选取有助于对构造进行定量化分析，确定构造形成时间与活动速率。

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This produced a ratio of active premium payers to recipients of 1. 8 to 1.

FORBES: Why the Bureaucracy Won't Reform Old Age Welfare

At the same time the ratio of active workers paying into the system to retirees drawing from the system has reached 1.86 to 1.

FORBES: Old Age Pensions 10 Percent of GDP and Rising

Today there are almost 700, 000 GM retirees and just 70, 000 active workers, a 10-1 ratio.

FORBES: GM Loosening The Noose From Its Massive Pension Plan