Answer:
-1.5
Explanation:
You take two of the variables in the pattern and subtract them with the second one being the minuend, and the first being the subtrahend.
For example we will use -4 and -5.5
(-5.5) - (-4) = -1.5
There is a negative sign present so it indicates subtraction towards the pattern.
Hence, the pattern change rate is -1.5