What is the proper way to determine the % of occurence of a specific member of a group?

Question

Example: 1000 jobs are completed by a Technician. 200 additional jobs were return visits on the original 1000 by the same Technician.

Is the proper equation for incomplete rate:200/1200
or:
200/1000

I want to determine the % of jobs that were not completed out of the total visits.

Answer 1

I don't think there really is a "proper way". The
"200/1200" conveys the information that for every 6 jobs the Technican goes out on, 1 will be a repeat vist. The "200/1000" conveys the information that for every 1000 initial visits, there will be 200 repeat visits. Whichever you like, you use.