There are also local factors, such as the concentration of internships in London, creating another hurdle for youngsters elsewhere in the country.

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The share of professional services jobs in the local economy is two and a half times the national average, the highest concentration in the country.

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The area is prone to changes in winds and local currents, and ships can quickly become trapped, sometimes for weeks, when the concentration of pack ice increases.

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Their concentration in particular cities, however, means that their impact can be more dramatic at the local level.

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