For example if it is 84% by the time I use its 78% (2 hours) another one is when I remove it from charging at night (100%) and in the morning (11-11:30am) 63 or 69%
Your battery will always slowly drain if the device is on, poor signal makes it worse.
At the rate yours is draining you've probably got an app eating up battery. If you go into your battery settings it will show you what's draining your battery.