The erratic fluctuation of market prices is in consequence of unstable economy.

经济波动致使市场物价忽起忽落。

《新英汉大辞典》

Selling the stock after the price rises and making money from prices fluctuation is speculative.

等股票涨价后卖掉，赚买卖的差价则是投机性的。

youdao

While neither production nor consumption take place, but people are engaged in trade, to buy is to sell and make money from prices fluctuation, which is speculative.

既不生产又不消费，但是从事买卖，买进就是为了卖出，从价差中赚钱，这是投机性的。

youdao

Prior to the housing collapse, fluctuation in house prices was the familiar story of supply and demand.

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As a result of the integration between the sugar and beverage businesses, Cultiba benefits from a natural hedge against fluctuation in sugar prices.

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For more sophisticated investors, or those with investing capital that exceeds a few hundred dollars, there are significant drawbacks to investing in gold-specific ETFs that go beyond the day-to-day fluctuation of gold prices.

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