ATS Corp. (NYSE: ATS) saw its stock plummet by 5.23% in pre-market trading on Thursday, following the release of its fiscal first-quarter earnings report. Despite beating overall estimates, investors appeared concerned about the year-over-year decline in adjusted earnings per share.

The automation solutions provider reported quarterly earnings of $0.30 per share, surpassing the analyst consensus estimate of $0.27 by 11.11%. Revenue for the quarter came in at $532.219 million, beating the expected $517.130 million by 2.92%. However, the adjusted earnings per share of CA$0.41 (approximately $0.30) fell short of the FactSet estimate of CA$0.44 and declined from CA$0.50 in the same quarter last year.

The market's negative reaction could be attributed to the year-over-year drop in adjusted earnings, despite the revenue growth. Additionally, ATS Corp.'s guidance for fiscal Q2 revenue, projected between CA$700 million to CA$740 million, may be viewed as conservative by some investors. This outlook, combined with the decline in adjusted EPS, appears to have overshadowed the overall beat on estimates, leading to the significant pre-market drop in share price.