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4 min read
Reading the Sector Map
A treemap compresses the whole market into one glance. Learn to read rotation, breadth and leadership from color and size.
Each cell is a company. Size is market cap, color is today's move. Green dominance means broad strength; a sea of red with a few green mega-caps means a narrow, fragile rally.
What to look for
- Breadth: are most cells the same color, or is it mixed?
- Rotation: which sector block is green when others are red?
- Leadership: are the largest cells (mega-caps) leading or lagging?