I will be the first to admit that I could be misunderstanding the C2 calculation, so I am looking for help understanding this.

Long story my ZIV trades from August 7th through March 23rd show a drawdown of nearly -18% which doesn’t make sense to me.

From August 7th all the way to February 24th I held at least 1 share of ZIV. From February 24th until March 19th I held 1 share of ZIV - less than 0.2% of my portfolio - while it dropped from about $70 to $31.36 at which point I bought 588 shares leaving me with 589 total with a cost basis very close to $31.36. One day later my indicators reversed and I sold 588 of my 589 shares for the price of $30.65 - a loss of about 2.3% of the position and much less of the overall portfolio. This left me with one share that I eventually sold three days later for $33.36. Now the low on the 20th of march was $30.17 as the screenshot shows. I do not understand how the drawdown as a % of equity shown is -17.95%. The drawdown listed is $15,307 which equated to about 17.95% of the total portfolio equity. However, I don’t understand how the cost basis needed to calculate a $15,307 loss from the worst ZIV price of $30.17 occurred.

FYI I was keeping 1 share of ZIV to keep trades private, but decided later that was unnecessary. Turns out had I kept that one share this metric would never have done what it did.

Here is a zoomed in equity curve for that timeframe too. There is a decent overall strategy drawdown before this timeframe but I only had 1 share of ZIV at the time and most of the drawdown was from TMF.