Does that mean you think coinmarketcap is scammy in their definition of ROI ?
What are you talking about ?
coimerketcap's definition is correct. Yours is wrong.
They have the cost of the Dash the denominator. You have the Dash itself on the denominator.
Are both ROI's calculated the same way ? Does coinmarketcap calculate their ROI % also as 'current value of investment - cost of investment divided by cost of investment' ?