Investors shaved $251.9 million off Xero's value on Friday after the company revealed its North American head, Peter Karpas, has stepped down after just six months in the job.
The accounting software company's shares fell $1.97 to $20.99 before recovering slightly to close at $21.10.
Mr Karpas was appointed in February after having previously worked at PayPal, where he was general manager of small and medium-sized businesses in North America, exactly the target market Xero is chasing.
He was touted as a key person in Xero's drive to take on its major competitor in the United States, Intuit.
Xero's founder and chief executive, Rod Drury, said Mr Karpas had helped establish strong foundations for Xero in the United States market.
Listen to Rod Drury