Their verdict is that public debt does little discernible harm until it reaches about 90% of a country's GDP, but then the effect on growth can be sudden and big.

他们的结论是，当公共债务还未占到GDP的90%之前，不会有多大影响，但是一旦超过90%，对经济增长的影响将是巨大和突然的。

youdao

Such fiscal adjustment may be necessary to ensure medium-term debt sustainability, but its immediate effect would lead to a reduction in private and public aggregate demand.

为了保持债务的中期可持续性，这些财政调节措施或许是必要的，但其短期效应将导致私人和公共部门总体需求的减少。

youdao

Yet the effect of these policies is essentially to add a new layer of public debt to the existing debt mountain.

不过，这些政策实际上会在现有的债务山上，叠加又一层公共债务。

youdao

If it grows even one percentage point faster than GDP in future, the effect on public-sector net debt would be huge (see chart).

ECONOMIST: The government paints a clearer picture

This would not only boost aggregate demand, but would have the pleasant side-effect of reducing the amount of debt held by the public, which could give Congress room to cut taxes or increase spending.

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