determine why my formula is incorrect

Job ID: 32085772

Budget: $10 – $30 USD

I made a spreadsheet that calculates the "Schaff Trend Cycle" stock trading indicator: (https://docs.google.com/spreadsheets/d/1NYGsuzIVGF0Sj4x7XlLDedCl0Tewa9DJZFf1Vx-KQJg/edit?usp=sharing) derived from the formula at this site: https://www.tradingpedia.com/forex-trading-indicators/schaff-trend-cycle. My calculations for the STC can vary above 100.

I also subscribe to a software package that calculates the values differently such that the values in the software "oscillate" between 0 and 100. The more I read about this calculation, the more I am convinced it is a bounded value between 0 and 100, so can someone take a look at my work and let me know why/how it is flawed? I'd like you to show specifically how my work is incorrect and make corrections to it so that it is correctly oscillating between 0 and 100. Outside references for the Schaff Trend Cycle are welcomed.

I suspect that the flaw may be due to an incorrect starting value, or something else, but I'd like an objective person who is gifted with mathematics take a look and then point out the problem! I need this done before I write a custom script for myself.