Conditional formatting task

This is the table....

Following  is the task...

A few government officials are
evaluating the course of development of that industry. They use the traffic
lights formatting. The officials set two indicators to separate excellent
(green), average (yellow), and poor (red) results.

Task
1: Which were the values they used to
separate green, yellow, and red variations? In 2015-2016, there were four green
lights, and in 2016-2017, there were four red lights. Also, Company G's
variation was marked as yellow in the first period and as green light for the
second period.

Task
2: Repeat the same task, but
consider, this time, the managers obtained five green lights in the first
column and only three green lights in the second. Company B had a yellow light
in the second column, and Company F had a yellow light in the first column.
These are the only yellow lights observed.

The solution to this as mentioned is 0.02 value selected for green and -0.02 for amber. I am unabme to understand how are these values derived for task 2
 I asked this question before also. What did he count.... And how did he derive.... Please can you explain... I am really struggling to understand this.