GM Captain.
Allow me to help you with a simple way of knowing this from now on without a calculator.
Take the amount it cost you. IN this case $400.
Then take the amount you sold it for. $1,000.
Subtract your cost from your sale price. $600.
Divide the amount of profit by the cost.
600 divided by 400 equals 1.50 or 150% You don't need a calculator my friend.. When we do not do things like this for long spands of time in our lives we all tend to forget so that is understandable. I just showed you a simple method you can do in your head from now on...
A refresher if you will..
That is a GREAT profit margin by the way... Congrats big time sir!!