The highest closing price for Costco Wholesale (COST) in 2021 was $542.07, on December 29, 2021. It was up 51.6% for the year. The latest price is $949.27.
Soleno Therapeutics (SLNO) had the highest return between August 1, 2023 and September 30, 2023 by a mid-cap US stock or mid-cap US stock, returning 490.2%.
Sorry, I don't have data available for that date. Qualcomm (QCOM) has a market capitalization of $185.5B, based on 1.11B shares at a price of $166.54 (down 1.8% yesterday).