How do you compare colors?
The most common method would be a visual color comparison by looking at two physical color samples side by side under a light source. Color is very relative, so you can compare colors in terms of the other color across dimensions such as hue, lightness and saturation (brightness).
What is the best way to compare two sets of data?
A Dual Axis Line Chart is one of the best graphs for comparing two sets of data. The chart has a secondary y-axis to help you display insights into two varying data points.