“市场是有效的”，就有利，“市场是无效的”，就不利——如果储蓄增加与否是市场自愿行为的结果。

这个问题很难回答，要考虑的情况很多，储蓄的增加对经济的影响既有利也有害，关键是达到一个平衡，一边是消费，一边是投资，储蓄是两者之间的连接，当然这只是简单的说法，随具体情况的不同而不同，如不同的金融机制（目前中国的金融机制在促进储蓄向投资转化方面的能力还很差），还有其他的体制原因，向美国那样的经济，主要靠消费拉动经济，储蓄多了不是好事，他不缺资金。

40％ .average.

In k system,GNP is divided by cosume and investment.and inverstment equal with S.that means high-rate S is key to the incerase of investment ,which finally push the increse of GDP.but,if the rate of S is too high,the present consume will be refrained.SO,keep the balance of S and I is important.and in the development economics,the rate of 40% is perfect for a nation,of course,the best rate should accord to the situation of one country.such as USA,the rate of S is too low!40% is average,especially for developing country!

黄金储蓄率

yes, cheak 黄金储蓄率 in solow model