The Correlation. Correlation is a measue of how close the line fits the points that you found in your experiment. Anyone can say whether they think the line is a good fit or not, but to measure it exactly, we use the correlation coefficient: R2.
As the seasons change and the amount of sunlight decreases, less chlorophyll is produced, and the leaves appear less green. Chlorophyll is broken down into simpler compounds at a constant rate, so green leaf color will gradually fade as chlorophyll production slows or stops.
Xanthophylls are yellow pigments, and carotenoids give leaves an orange color. Photosynthesis also uses these pigments during the summer, but chlorophyll, a stronger pigment, overpowers them. These pigments take more time to break down than chlorophyll does, so you see them become visible in fall leaves.