From original source:
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This hourly data set contains the PM2.5 data of US Embassy in Beijing. Meanwhile, meteorological data from Beijing Capital International Airport are also included.
Additional Information
The data's time period is between Jan 1st, 2010 to Dec 31st, 2014. Missing data are denoted as "NA".
Has Missing Values?
Yes
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Columns with index 0 were deleted from the dataset, usually because they related to some kind of index.