According to comScore reported holiday season US retail e-commerce spending from desktop computers for the entire November-December 2015 holiday season, $56.4 billion was spent online on desktop computers, marking a 6-percent increase versus the corresponding days last year.

Cyber Monday (Monday, Nov. 30) once again ranked as the heaviest spending day of the year with more than $2 billion in desktop buying for the second year in a row.

Total digital spend for the holiday season, when inclusive of comScore’s preliminary mobile commerce estimates, reached $69.1 billion, about a 13-percent annual gain vs. $61.3 billion spent in the 2014 season. Mobile commerce is estimated to have accounted for 18 percent of total digital commerce in November-December 2015, an increase from 13 percent in the previous season. A total of $12.7 billion was spent via smartphones and tablets during this period, up a staggering 59-percent versus year ago.

comScore’s holiday season forecast had expected desktop e-commerce to grow 9 percent to $58.3 billion and mobile commerce to grow 47 percent to $11.7 billion. While desktop spending fell short by 3 percentage points and $1.9 billion, preliminary mobile estimates suggest it exceeded forecast by 12 percentage points and nearly $1 billion, helping to offset the shortfall on desktop.

“Despite falling slightly short of our original forecast of 14 percent growth, the 2015 online holiday shopping season was nevertheless very successful with growth rates well into double digits and once again far exceeding that of brick-and-mortar,” said comScore chairman emeritus Gian Fulgoni. “Fairly early on it became clear that desktop e-commerce would likely underperform our expectations while mobile commerce was poised to over perform, but for the most part signs continued to point to hitting that 14-percent overall growth estimate. Where the season ultimately fell short was in the last two weeks of the year, and in particular the week before Christmas. We had anticipated heavy desktop spending through Free Shipping Day on December 18th that unfortunately did not materialize, and spending began to soften more than expected by the Wednesday of that week.”

Fulgoni continued: “If there is an underlying takeaway from this holiday season, I think it will be remembered as the one where ‘mobile ate brick-and-mortar.’ Mobile became an essential shopping channel nearly doubling desktop in total retail traffic, while seeing growth rates approaching 60 percent year-over-year at the same time that offline retail experienced softness throughout the season. I believe that we’ve seen a paradigm shift in 2016 where the future of retail will increasingly be defined by consumers’ behavior on mobile.”

Cyber Monday (Nov. 30), for the sixth consecutive year, ranked as the heaviest online buying day with $2.28 billion in desktop spending. The day after Cyber Monday ranked second for the season at $1.95 billion, followed by Black Friday (Nov. 27) with $1.656 billion and Friday, Dec. 11 with $1.477 billion. For the entire season, sixteen individual days exceeded $1 billion in online spending via desktop, an increase from fifteen the previous year.