Investors rolled into shares of Apple in September, according to TD Ameritrade, but took profits on shares of Bristol-Myers and Pfizer shares.

Investors bought shares of Apple (AAPL) - Get Report in September and sold Bristol-Myers (BMY) - Get Report and Pfizer (PFE) - Get Report , according to fresh data from TD Ameritrade.

JJ Kinahan, TD Ameritrade's chief market strategist, pointed to Apple's new iPhone announcements as reasons for investor interest in the stock. Plus, Bristol-Myers and Pfizer both reached 52-week highs in September, prompting investors to take some profits in the stock.

Plus, amid the record run in the the broader stock markets, Kinahan expects investors to continue the "buy on the dip" strategy.

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