Git USES an internal index to track the state of the files and directories in a repository.

Git使用内部索引跟踪文件的状态和存储库中的目录。

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ETFs are quoted securities that track a particular index, for a fee that is normally just a fraction of a percentage point.

ETFs是跟踪某种特殊指数进展的上市证券。它的费用通常不到百分之一。

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To track the index, the ETF holds shares in 55 companies, more focused on gas than oil.

FORBES: New 'Wildcatters' ETF Takes the Fun Out of Small-Cap Energy Investing

This makes it difficult to ensure a bond ETF encompasses enough liquid bonds to track an index.

FORBES: An Easy Way To Add Fixed-Income To Your Portfolio

This is an excerpt from the February 25th, INSIIDE Track Stock Index Update.

FORBES: Uncanny 16 Month Stock Cycle Points To Major Decline