is the best performance from either in years 
(ROOT (VP (VBZ is) (NP (NP (DT the) (JJS best) (NN performance)) (PP (IN from) (NP (CC either))) (PP (IN in) (NP (NNS years))))))
(ROOT (VP (VBZ ) (NP (NP (DT ) (JJS ) (NN )) (PP (IN ) (NP (CC ))) (PP (IN ) (NP (NNS ))))))