E-commerce has been upending the retail industry over the past few years, and retailers are desperately trying to figure out the happy medium of how many stores they need to operate and how much to invest in e-commerce. 
And, if comScore's latest U.S. e-commerce data is any indication of what to expect this year, e-commerce sales will continue growing at a rapid pace. BI Intelligence has prepared the chart below, showing how e-commerce sales have trended since 2008.
  • PC-based e-commerce spending in the U.S. grew 12% year-over-year to $56.1 billion in the first quarter of 2014. This is the fourteenth quarter in a row that desktop-based e-commerce spending has grown by double digits.  
  • Mobile-based e-commerce spending grew 23% year-over-year to $7.3 billion in the first quarter.
  • PC-based spending accounted for 88.5% of all e-commerce purchase volume in the first quarter. For comparison, PC-based spending accounted for 89.5% of all e-commerce spending in the first quarter of 2013, so mobile is taking up a bigger share of online purchases. 

bii us ecommerce spending comscore
BI Intelligence