20162015201420132012
Avg order size$186$175$169$158$135
Customer orders (M)11,44510,99710,1929,2689,079
Unique customers (M)7,9687,8437,5257,1237,041
New customers (M)N/A3,6823,7043,5243,371
Cost per Customer$18.56$15.87$14.55$12.86$9.01

Notes:Cost per customer equals sales and marketing spending divided by the number of unique customers during the period