underperforming

/AH1 N D ER0 P ER0 F AO0 R M IH0 NG/
verb
  1. 1

    To underachieve, to not reach standards or expectations, especially with respect to a financial investment.

Antonyms

adjective
  1. 1

    That performs less well than required

Source: https://en.wiktionary.org/wiki/underperform, https://en.wiktionary.org/wiki/underperforming