Walmart shares were on course for their worst day of trading in over two years after the company reported disappointing results.
Shares were down by 9.4% in New York trading as at 17.48 GMT, erasing more than $28bn from the group´s stock market valuation.
Analysts were especially disappointed by a sharp slowdown in Walmart´s online sales growth in its fiscal fourth quarter.
Slower online growth
While online sales were up 23% in the quarter versus the year-ago period, this was markedly slower than the 50% growth from the online sales channel that the US retail giant enjoyed over the first nine months of its 2018 fiscal year.
The results raised concerns that Walmart was still struggling to compete with e-commerce giant Amazon.com.
Walmart revealed that part of the slowdown in volumes was due to difficulties in meeting supply demands at its online distribution hubs.
However, it also said weaker profit margins were due to price cuts as it attempted to compete head-to-head with Amazon.com.
There were also higher costs owing to rising oil prices.
Excluding special items, quarterly earnings came in at $1.33 per share, well below analysts´ expectations of $1.37 per share.
Net income fell 42.1% to $2.18bn from $3.76bn.