By early afternoon, shares had slid 4.8% to $49.80.
The healthcare tech company said it expects adjusted earnings for its June-ending second quarter between 39 cents and 40 cents a share. Analysts surveyed by Thomson Reuters had estimated 40 cents a share.
For its full year, earnings are expected between $1.63 and $1.67 a share, with analysts estimating net income at the high end of that range.
Over the three months to March, Cerner earned 37 cents a share and revenue of $784.76 million, inline with analysts' estimates.
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