i-1 But with index i minus 1.

但是同时返回的是索引号。

麻省理工公开课 - 计算机科学及编程导论课程节选

On Thursday the Philadelphia Federal Reserve Bank noted that factory activity in the mid-Atlantic region continued to slow in June with its index posting minus 17.1 compared to 15.6 in May.

FORBES: Economy Still Underachieves

The index for finished minus food and energy surged .4%, the largest increase since last July.

FORBES: Falling Jobless Claims & More Positive Data Prompt Futures Rally

The economic-expectations index fell to minus-16.9 in June from 10.8 in May, against expectations for a reading of 2.8.

WSJ: Europe Stocks Rise