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if all values are negative the winner will be the one which has loss as close to zero as possible more like if you have -1% you go from 100% to 99% and when you have -10% it goes from 100% to 90%.....
now the i am using are 24hr charts......which compares the current values of currencies to the values which were 24hrs before.....You can also get weekly chart or yearly when it will compare the current price with that of year or week ago and give you the corresponding growth or loss

Historical data tab on is in daily values on coinmarketcap.

can you tell me little clearly wat exactly is your doubt ? i hope all my conversation has cleared your concept about what is profit and what is loss

please read all the conversation ones more it will help you to understand the concept and if you have any doubts you can ask me anytime