As shares of global tech giant Apple Inc. (AAPL) dropped more than 6% in September, one team of analysts warns on further downside, suggesting that Wall Street’s expectations for the new iPhones “are pricing in more than Apple can chew.”

Deutsche Bank reiterated a hold rating on shares of Cupertino, Calif.-based Apple on the belief that analysts have overestimated potential iPhone FY19 sales. In a research note on Wednesday, Deutsche analyst Sherri Scribner wrote, “we remain wary that investor expectations for the iPhone 8/X cycle are more optimistic than realistic.” (See also: Apple Just Bottomed, If You Blinked You Missed It.)

iPhone Shipments Underwhelm

The Deutsche analyst says that investors are hoping for another blowout upgrade cycle in fiscal 2018, similar to that of the iPhone 6 upgrade cycle in 2015, when the company posted sales $31 billion above expectations. To surpass the Street’s forecasts by the same amount, the current cycle would require Apple to ship 45 million more iPhone units in FY18​ than currently expected, or nearly 290 million iPhones, wrote Scriber. “We view this as highly unlikely.”

She suggests that estimates need to come down to realistically reflect a year after a strong cycle, adding that the investment firm sees “modest downside risk to shares near-term.” As for fiscal 2019, the Deutsche analyst is even more bearish, expecting Apple sales to drop off. Scribner has a $140 price target on AAPL, expecting shares to fall about 9.2% from current levels.

Closing up 0.6% on Friday at $154.12 per share, AAPL reflects an approximate 33.1% gain year-to-date (YTD) versus the S&P 500’s 12.5% rally over the same period. (See also: Apple, Amazon, Google, Facebook Still a Steal: MKM.)

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