E-commerce sales remained strong in 2015 as web sales totaled $341.7 billion for the year, a 14.6% increase over 2014’s $298.3 billion, according to non-adjusted estimates released this morning by the U.S. Department of Commerce.

Total retail sales grew 1.5% on a non-adjusted basis to $4.71 trillion from $4.64 trillion, when factoring out foodservice sales and sales at restaurants and bars. Online sales accounted for 7.3% of total retail sales in 2015 versus 6.4% in 2014, and e-commerce accounted for 60.4% of total retail sales growth.

When further factoring out sales of automobiles and fuel—items not normally bought online—total retail sales grew by $120.2 billion (3.8% year over year) to $3.25 trillion from $3.13 trillion in 2014. E-commerce, on the other hand, grew by $43.5 billion last year on a non-adjusted basis, which means online sales accounted for 36.2% retail sales growth.

By this definition, e-commerce comprised 10.5% of retail sales in 2015 versus 9.5% in 2014.

On an adjusted basis, full-year web sales were $340.8 billion.

The largest e-retailers in North America are responsible for the vast majority of these online sales. Merchants ranked in the Internet Retailer Top 1000 represent 85.7% of online retail sales in the U.S. They collectively grew U.S. sales 14.0% in 2015 to $293.15 billion from $256.16 billion.

This is the sixth year in a row that U.S. e-commerce sales have grown near or above 15%.

For the fourth quarter, retailers sold $107.1 billion online, a 14.5% increase over $93.5 billion in Q4 last year, and an amount that represents 31.3% of full-year e-commerce sales.

Adjusted for seasonal variations, holiday and trading-day differences, the Commerce Department estimates Q4 web sales reached $89.08 billion, up 14.7% from $77.66 billion a year earlier. On an adjusted basis, e-commerce accounted for 7.5% of total Q4 retail service excluding foodservice, up from 6.6% in Q4 2014.