Amazon.com Inc. nabbed 37.5% of online sales in the final two months of 2017, according to e-commerce analytics firm Slice Intelligence.

Slice analyzes U.S. online sales based on the email receipts of a panel of 5 million online consumers. This does not include app sales.

This 37.5% is only a half percentage point increase from the 2016 holiday season, when Amazon, No. 1 in the Internet Retailer 2017 Top 500, accounted for 37.0% of 2016 holiday sales. While the market share is roughly the same, overall online sales have increased, which means the retailer generated a larger sales volume than it did in 2016.

After Amazon, the websites for Best Buy Co. Inc. (No. 10) had the next-largest market share at 4.74% of sales, Target Corp. (No. 20) had 2.97%, Wal-Mart Stores Inc. (No. 3) had 2.48% and Apple Inc. (No. 2) was at 2.36%.

Amazon’s dominance in the holiday season was more pronounced in December than it was in November, according to Slice data. Amazon accounted for 31.9% of e-commerce sales in November and 40.6% of sales in December.

“Amazon’s biggest share gains can be in the period after Cyber Monday and peak the Monday before Christmas, validating the hundreds of millions of dollars that Amazon continues to spend on fast fulfillment,” says Ken Cassar, principal analyst for Slice.

Slice finds that for the entire year, Amazon’s high point for market share—41.7%—came in July, which is likely because of its own shopping holiday, Prime Day. December ranks second for market share for Amazon.

For all of November and December, shoppers spent more online this year, according to Slice. Online shoppers spent an average of $637.77 during the 2017 holiday season, $62.03 more than in 2016, when online shoppers spent an average of $575.74.

Slice also estimates that the number of online shoppers increased 12% year over year.

Cyber Monday edged out Black Friday in terms of online holiday sales, accounting for 4.8% of total online sales during the holiday season while Black Friday accounted for 4.7%. Those two days were the largest online sales days of the holiday season, and the biggest days were the six days from Thanksgiving (Nov. 23) through the Tuesday (Nov. 28) after Cyber Monday.