fluctuate
US /ˈflʌk.tʃu.eɪt/
UK /ˈflʌk.tʃu.eɪt/

1.
fluctuer, varier, osciller
rise and fall irregularly in number or amount
:
•
The stock market prices fluctuate daily.
Les prix du marché boursier fluctuent quotidiennement.
•
Her mood often fluctuates between happiness and sadness.
Son humeur fluctue souvent entre le bonheur et la tristesse.