In this case, the percent if change is a percent decrease because the original was decreased by 11 to get the new.
To find the percent of change,take:
11÷55=0.2 or 0.2×100=20%.
Or
You can take:
44÷55=0.8 or 80%
Then,
100%-80%=20% to get the percent of change. As a result, the percent of change is 20%. Hope it help!