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Top Stories: most viewed stories published in the last 3 months.
Trending: looks at "last" 2 hours. Displays articles that have more views in the last hour than in the hour before. Hours are fixed, not rolling blocks, e.g. 3:00-3:59, 14:00-14:59. There is no publish date limit. Example: At 3:12pm, trending articles are articles that have more views during 2:00PM-2:59PM hour than 1:00PM-1:59PM hour (AND also had views in 1:00PM-1:59PM hour)
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