Because the sample of households is small relative to the total number of households, the series is notoriously volatile.

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Refining margins are notoriously volatile, which is why companies that primarily operate refineries often trade with comparatively lower multiples.

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Food and energy, driven by (notoriously volatile) commodity prices, can experience short-lived supply disruptions tied to weather, geopolitics, technology failures, etc.

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Trading expert Justin Urquhart Stewart, director of Seven Investment Management says betting on movements in foreign exchange rates is notoriously volatile.

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In a bid to unlink Punj from the notoriously volatile energy sector, Atul has expanded into infrastructure, a crying need in India.

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What remains to be seen is whether Freescale's private-equity backers tough it out in the notoriously volatile semiconductor business or try to break up the company and stem their losses.

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Investment banking is notoriously volatile, but there is reason to worry that it won't bounce back as quickly as it did after the downturn that followed the bursting of the dotcom bubble in 2000.

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Kevin Daly of Goldman Sachs thinks there are modest grounds for optimism: the sectors that shrank most this time, such as oil and gas, are notoriously volatile, whereas those that grew, such as services, may be seeing sustainable improvement.

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Technology stocks are notoriously volatile.

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This category is notoriously volatile.

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