In this task you will be given a list of numbers and you need to find the mean (average) of that list. The mean of a list can be found by summing every number in the list then dividing the result by the size of that list. The output should be rounded to 3 decimal places.
[-49.922, 96.2, -24.223, 126.909, 168.393, -55.73, -51.195, 92.652]