Covering indexes allow data storage within the index itself while sparse indexes exclude documents that do not contain the missing field.

Covered索引允许在索引本身里存储数据，而Sparse索引则会排除掉不包含索引字段的文档。

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The index is a combination of three sub-indices covering wealth, health and education.

该指数由3个次指标组成，涵盖了财富，健康和教育领域。

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The price-earnings ratio of the index, covering both the Shanghai and Shenzhen Exchanges, has dropped from the highest point of 53 times to the current 14.36 times, the lowest point since 1995.

沪深300的市盈率已由最高点的53倍跌至目前的14.36倍，为1995年以来的最低水准。

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Earlier this month, the index covering the Mumbai exchange touched levels not seen since February 2001, having climbed by more than 50% since April.

ECONOMIST: India's economy

Japan accounts for the largest country weighting in the MSCI EAFE (Europe, Australia, Far East) index, a global stock index covering more than 20 countries.

FORBES: When All Else Fails, Go Long

The ISM Non-Mfg Index, covering the services sector, also declined in March.

FORBES: Stock Market Warning Signs Becoming Ominous