Brand new iPhones do discharge the battery quicker for various reasons. New batteries need to go through several charge and discharge cycles to reach full capacity. When data is transferred from an older iPhone there are literally hundreds of background processes that are running and consuming additional battery capacity.
Depending on your usage patterns this may take up to 72 hours or in a few instances even longer.
How long have you had you iPhone and please share a few screenshots of your recent battery performance such as mine below.

