Apple Inc.’s customers will nearly double their spending on the company’s services offerings, such as Apple Pay and Apple Music, in the coming years, an analyst predicted Monday, meaning billions more in profit for the iPhone maker.

Credit Suisse analyst Kulbinder Garcha conducted an analysis into Apple’s business and reported that investors might be underestimating and underappreciating the growth potential of services such as Apple Pay, Apple Care, Apple Music and iCloud.

Garcha estimates that gross profit related to services has grown to about $14.5 billion from $3.2 billion in 2010, and sees that more than doubling to nearly $34 billion by 2020. The amount each user spends on such services is expected to skyrocket by 85% to $113 a year by 2020 from roughly $61 today, helping to lift its share of Apple’s total profit to 29% from 15%—a number that could rise if Apple were to launch a TV service.

“It would be naive to assume that Apple will not enter the TV streaming business at some point and capitalize on more opportunities in the gaming segment as well,” Garcha said.

Garcha upped his price target on the stock to $150 from $140, reiterated a buy rating and added the stock to the bank’s “U.S. Focus List” of top investment ideas. Shares of Apple AAPL, -3.17% rose 1% to $111.12 on Monday, pushing the price up 8.2% over the last three months, vs. a 4% increase for the Dow Jones Industrial Average. The shares were down 1.3% in premarket trade on Tuesday.

Apple has relied on strong hardware sales, notably the iPhone, for the vast majority of its growth in the past few years. The iPhone accounted for 66% of Apple’s total revenue in fiscal 2015. However, saturation in the hardware market has increased the need for additional sources of revenue.

Analysts expect Apple to sell 50 million smartphones in the fiscal second quarter, which would mark a year-over-year decline—the first ever for the product—from 61 million in the year-earlier period, according to FactSet. Total revenue related to iPhones is expected to shrink to $33 billion from $40.2 billion last year, and Garcha believes the iPhone business will contribute just 38% to gross margin by 2020.

With Apple’s installed base of more than 1 billion devices, software services are seen as supplementing some of the slowdown in device sales as Apple homes in on an affluent user base willing to pay for premium services.

Apple emphasized the importance of this growing market on a call with analysts in January. Apple Chief Executive Tim Cook said the growth of the company’s installment base has accelerated the pace of service sales.

Cook called services another “large and important source of recurring revenues” for Apple, with the aggregate purchase value of services tied to the company’s installed base climbing 23% year-over-year to more than $31 billion in fiscal 2015.

“We have tremendously satisfied and loyal customers who are engaged with our services at a fast-growing rate,” Apple Chief Financial Officer Luca Maestri said on the call with analysts.

Garcha estimates Apple has a user base of 588 million active and “highly affluent” consumers, and believes the company can “conservatively” derive 55% of gross profit from annuity-type businesses, such as services and the iPhone installment and upgrade plans, by 2020.

While Apple’s growth has historically been based on actual point of sale hardware units, the installed base actually presents “a largely reoccurring cash flow stream,” he said.