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I just came across the following sentence;
A company with 1,000 employees who each send eight e-mail messages per workday would produce two million messages per year.
where who each send sounds incorrect. "who each send" (used in Google-Books)
After I tried to compare "who each send", and "who all send" on Google-Ngrams, no ngram was found for the first one. So, is it grammatical?