While Costco Wholesale (NASDAQ: COST) suffered from slowing sales growth for much of 2016 and early 2017, the warehouse club giant has bounced back in a big way over the past year. During that period, Costco has routinely posted mid-high single-digit adjusted comp sales growth.Last month, Costco posted yet another strong sales performance despite headwinds from the timing of Easter and a tough year-over-year comparison.