hold down

to keep something, especially costs, at a low level:
to hold down prices/wages
(Cambridge Advanced Learner's Dictionary & Thesaurus からの hold sth down の定義 © Cambridge University Press)

ビジネス英語
to keep something at a low level or to prevent it from rising:
The Fed held down interest rates to encourage growth in the economy.

to be able to keep a job:
He couldn't hold down a job for more than a few months at a time.
She had three children, and still managed to hold down a full-time job.
(Cambridge ビジネス英語辞典 からの hold sth down の定義 © Cambridge University Press)

- Cambridge Dictionary