Amazon’s sales growth continued in 2017, with revenue jumping 31% in the year over 2016, reaching $177.9 billion. Its earnings performance was another story, with operating income falling 2%, to $4.1 billion, while net income rose 25%, to $3.0 billion.

Amazon’s results gave no real visibility to how its book business performed. Sales of products, which includes books, rose 25.5% in the year, to $118.5 billion. Service revenue jumped 44%, to $59.3 billion.

Among the many numbers the company touted, was 5 billion; that figures represents the number of items Amazon shipped with Prime worldwide. The division that handles this function, Fulfillment By Amazon (FBA), shipped “billions” of items for third party sellers, the company reported. Amazon also said that, since it launched the Kindle in November 2007, it has sold “tens of millions” units of the device.

Amazon sees its financial performance being much the same in this year’s first quarter as it was for all of 2017—big sales gains offset by a soft earnings performance. Revenue is forecast to increase between 34% and 42% over the first quarter of 2017, but operating income will be between $300 million and $1.0 billion, the same figure Amazon posted in last year’s first period.