Hayward Holdings shares rallied Wednesday. The pool equipment manufacturer is set to join the small-cap focused S&P 600 on Friday before trading opens, according to S&P Dow Jones Indices.

Hayward shares rose 9%, on pace for their largest daily percentage gain since January. The company will take the spot of Civitas Resources, which join the mid-cap heavy S&P 400.

Syneos Health, a constituent of the mid-cap index, will be kicked out to make room for Civitas.

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