Chipotle Mexican Grill Inc (NYSE:CMG) , the burito chain, saw shares plunge nearly 7%, making it the worst performance on the S&P 500 , as its latest regulatory release did little to stem investor fears over the stock.
The fast food group has been beset with issues in recent years including hacking and an e-Coli outbreak, and now it has worried by talking increased marketing spend.
In its first quarter, the firm saw same-store sales rise almost 18%, the first increase in more than a year.
In February, it had told investors it has speeded up wait times at its outlets with a new digital rollout.
But now the firm said it expected marketing and promotional costs to rise by 0.2 to 0.3 percentage points in the current quarter, compared to the previous one, to 3.6 to 3.7% of sales
Shares fell 6.72% to $428.05.