What is the sentiment of this news? Please choose an answer from {strong negative/moderately negative/mildly negative/neutral/mildly positive/moderately positive/strong positive}.
Text: Costco (NASDAQ: COST) stock, the second largest warehouse club operator in the U.S. behind only Walmart's Sam's Club, has increased by 13% over the last twenty-one trading days (one month) and currently stands at around $516.
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moderately positive
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