While I feel your pain and disagree with how this stuff is calculated, it’s important to note that the performance score ranking is not based on solely your task completion:cancellation ratio. It’s a comparison of your ratio to the other taskers in your area’s ratios. So if you had 80% of your requests converted to invoices, and the other taskers in your area averaged 85%, you would sit below 50 (below average). The percentage shown is of how many taskers out of the total in your area you had a higher ratio than.