Return percentages?

So question about the Cumulative return percentage, and the monthly return percentage.

I’ve been here for a month and see 67.3% cumulative return, but under the monthly stats it shows July 118.7% and so for for August -20.2%

Wouldn’t this suggest that my cumulative return should show 98.5%?
Obviously as time goes on, calculating this number becomes more complicated, that’s why I’d figure to ask about it now

Which then also leads to the chart, for some reason the study shows starting with $6K (it was $5K, don’t know when this changed) but. I started with $30K.

The buying power shows $64,157, yet the chart shows $50,198. That’s a huge difference.

Which is the correct number to go buy? Shouldn’t the buying power be reflected in what other users see?

Put in all the data through a spreadsheet and calculated the data, the cumulative return percentage is correct.

But anyone know why there is such a huge variance with the buying power?
Is this also taking in account for margin?

This is common misconception about return percentages.

When you have monthly returns that look like this:

Month 1: a%
Month 2: b%
Month 3: c%

… then the year-to-date is NOT A%+b%+c%. (Plug in real values to excel or a calculator, and try out the math to see why.)

This is related to the old investing observation that, if you lose 10% of your account in one month, you’ll need to gain more than 10% in the following month just to get back to break-even.

Yea I thought about that after I posted it, ran it all through a spreadsheet and the cumulative percentage matched.

What about the buying power? There is a big difference between that and what the chart shows. The chart value is correct

Guys, I am new to C2. I have a simulation account that shows on my allocation a 4% all time change on $12,953 gain from a $129,800 starting position.
Anybody knows how this percentage change is computed?