Not every day you can earn 1%, sometimes if you fall on a black day you can lose 10%, as if you have lost 10 days to accumulate 1%. Measurement is difficult.
Bitcoins are unstable and that is why your profits or losses cant be specific. This loss or profit can be around your 1% but not exactly this. And like you have said, definitely sometimes you are going to have profits and sometimes it is loss that you have to bear.
So the loss ratio can vary %5 or %10 or even more. Same is the case with bitcoins. You can get 1% exactly or even more but not every day.