President Donald Trump is not convinced of changing the current daylight saving time system, calling it a “50-50 issue” even as the modification has been floated by one of his top advisers.

On Sunday morning, the country, with the exceptions of Arizona and Hawaii, will move from standard time to daylight saving time as part of the biannual time adjustment. The changeover typically renews the debate on whether standard time should remain permanent rather than changing the time twice a year.