In this task you are given a list of numbers and you need to find the average of each two consecutive values. The average of two numbers a and b is calculated as: (a + b) /2. The output should be a list of the averages of each two consecutive values. A list is presented with two brackets and comma-separated values, like: [1,2,3].

[-83, 35, 74, -77, -32, 67, 98, -18, 73]

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
[-24.0, 54.5, -1.5, -54.5, 17.5, 82.5, 40.0, 27.5]