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].

[34, -69, -58, 24, 76, -97, -36, -74, 75, 56, 87]

[-17.5, -63.5, -17.0, 50.0, -10.5, -66.5, -55.0, 0.5, 65.5, 71.5]