It was a record-breaking Holiday season for e-commerce in 2016, with retailers raking in a staggering $91 billion in sales. That’s up from roughly $82.5 in sales the previous year. Of course, online Shopping is growing and e-commerce is expanding, but beyond that, there are a number of factors contributing to this dramatic increase in online sales. So, why did online shopping rates skyrocket this holiday season? Let’s take a look.

Amazon is expanding. Amazon called the 2016 holiday shopping season its best ever, announcing that it had shipped over 1 billion items worldwide via both its Amazon Prime and Fulfillment by Amazon services. Fulfillment by Amazon services allow third-party sellers that are on the Amazon marketplace to use the company’s logistic network to deliver their orders. Last year, Amazon sent out less than 200 million items via Amazon Prime throughout the holiday season, so with Fulfillment by Amazon the company was able to drive even more online purchasing. Ultimately, Amazon is becoming increasingly important in driving online sales.

Shipping prices are down. Increasingly, retailers are offering free or reduced price shipping in order to lure customers into making purchases online. For example, average holiday shopping costs per an order were $2.50 in 2016 compared to $2.60 in 2017. As shipping prices continue to fall, online shopping continues to become a more attractive option to customers.

Customers are planning out the purchases they plan to make online in advance. Customers are increasingly leveraging the power of their smartphones as tools in planning their holiday shopping. All in all, mobile phones and tablets drove half of all web visits during the holiday season, accounting for just under one-third of purchases, and generating close to $29 billion in sales, up 23 percent from last year. In order to cash in on this consumer behavior, retailers need to make sure that they make it easy for their customers to browse items and plan for their purchases online. The better they do so, the more they stand to gain from the remarkable shift towards online shopping.

In conclusion, a number of different variables are influencing this seismic shift in consumers’ shopping patterns. The quicker retailers can adjust, the more money they stand to earn, particularly once the 2017 holiday shopping season rolls around.