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Pivot table to find max, min, avg temp in large data set

I have 6 years of data, temperature recorded in 15 min increments. I’d like to find the max, min, avg by month (so max temp from all januarys, max from all feb. etc.) When I plot the pivot table I get “0” in the value field. I plot Month_2 as the row and Value as the “value”.

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