Your end date would be 12/31/2021 if you still worked for that employer on 12/31/2021. Michigan is looking to account for all days of 2021.
If you held multiple jobs during 2021, you will need to enter the start and end dates for each job you held. One of the jobs will or should have an end date of 12/31/2021. However, if your end date was before 12/31/2021 and you did not start another job before 12/31/2021, then whatever the date was on the last job you worked would be the end date for the year.
@devonna1972
