Out of 104 IRISL-linked cargo ships surveyed, 62 ships, or 60%, of the total sample, are currently in or near Iranian ports.

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Percentages below are based on a total sample 5300 likely voters.

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By contrast, in July, 2010, in a pattern that until a few months ago appeared roughly the norm, only 28 of these ships, or 27% of the total sample, were in or near Iranian ports.

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Although the findings of the studies are mostly consistent in showing a similar magnitude hazard ratio, estimates of the effectiveness of sipuleucel-T are imprecise due to the relatively small total sample size of the clinical trials, and unmeasurable biases due to potential confounding effects of frozen salvage product and post-progression treatments.

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This sentiment was echoed in the report, which stated that only 1.3% of the companies had a female founder, 6.5% had a female CEO, and 20% had one or more female C-level executives, most commonly in sales and marketing roles - accounting for 27% of the total population sample.

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

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Albert Esteve of the Autonomous University of Barcelona reckons that the total number of cross-border marriages among 25-39-year-olds in his sample was about 12m in 2000.

ECONOMIST: International marriage