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Frequency of extremely dry (SPEI ≤−1.6) and extremely wet (SPEI ≥ 1.6) conditions from 2001 and 2013.
Note: Districts excluded from analysis include: i) those that were composed solely of urban areas (n=16), ii) island territories (n=3), and iii) districts that had data sources that could not be successfully linked (n=6).
