What is the best way to calculate the effectiveness of a remote worker?

Question

Work organization

What is the best way to calculate the effectiveness of a remote employee, based only on the set, completed, overdue tasks? Now the formula is

100 - (Notes on tasks / Tasks in progress) * 100

Comments on tasks - the performer or co-executor was given a task and he missed it. deadline has expired
Tasks in progress - in a certain period, the number of open and closed tasks

Answer 1

This does not work. Programmers are usually smart guys, and they know how to adapt to any KPI.
https://blog.sibirix.ru/2012/09/26/kpi-as-genocide/