Given the task definition and input, reply with output. 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].

[-99, 92, -11, -76, 9, -3, -67, -70, 11, -16, 71]

[-3.5, 40.5, -43.5, -33.5, 3.0, -35.0, -68.5, -29.5, -2.5, 27.5]