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].

[-55, -7, 47, -29, -31, 74, 23, -55, -92, 43, -100, -98, -77]
[-31.0, 20.0, 9.0, -30.0, 21.5, 48.5, -16.0, -73.5, -24.5, -28.5, -99.0, -87.5]