"i'm sorry detective, my responses are limited, you must first ask the right question...."
what are you measuring? maybe it would help if you posted a schematic, and explained what you are trying to do. there isn't enough information in your post to give you a rational answer. average power depends on magnitude and time. you can have extremely low average power with huge peak power, so a simple divide by 2 doesn't work unless you have a 50% duty cycle. 2 watts peak with a 50% duty cycle is 1 watt average power. 10 watts peak with a 10% duty cycle is also 1 watt average power, and 100W peak with 1% duty cycle again is 1W average power.