This design is more complex than the other two options since the system will have to track two time intervals.

该设计比其它两个选项更复杂，因为系统将不得不跟踪两个时间区间。

youdao

Having spent thirty years recording my time in 15 minute intervals, the concept of a project extending over two decades is mind boggling.

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If the market is in a bear cycle, try dollar cost averaging (especially for larger portfolios), but keep the time frame relatively short, no more than three months, preferably in two week intervals between buys.

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