The lifetimes of the first excited 2 þ states in the N ¼ Z nuclei 80 Zr, 78 Y, and 76 Sr have been measured using the γ-ray line shape method following population via nucleon-knockout reactions from intermediateenergy rare-isotope beams. The extracted reduced electromagnetic transition strengths yield new information on where the collectivity is maximized and provide evidence for a significant, and as yet unexplained, odd-odd vs even-even staggering in the observed values. The experimental results are analyzed in the context of state-of-the-art nuclear density-functional model calculations.

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