Normalized SP100/SP400 Ratio with Shiller PE Ratio (CAPE Ratio)

This indicator is designed to observe market concentration and overall valuation by combining the Shiller CAPE Ratio with the SP100/SP400 ratio.

Blue Line: Represents the Shiller CAPE Ratio, which reflects the overall market valuation.
Yellow Line: Represents the SP100/SP400 ratio, which indicates market concentration.
The combination of these two metrics provides insight into market dynamics. Historically, on the SPX monthly chart, when the yellow line (SP100/SP400 ratio) crosses below the blue line (CAPE Ratio), it has been followed by a period of stock market gains.

Justification for Combination:

The Shiller CAPE Ratio is a widely recognized indicator of market valuation, providing a long-term perspective on whether the market is overvalued or undervalued. The SP100/SP400 ratio, on the other hand, measures the concentration of the market by comparing the largest 100 companies to the next 400 mid-sized companies.

By normalizing both metrics and analyzing their relationship, this script provides a unique perspective on market movements. The crossunder of the SP100/SP400 ratio below the CAPE Ratio may signal a shift in market sentiment or concentration, often leading to potential market rallies. This combination is not just a simple merger of indicators but rather a thoughtful integration that adds value by highlighting periods where market concentration and valuation dynamics align.