Dormant database user accounts

We are currently having a discussion in house about user accounts in the databases that are considered 'dormant' or unused. I want to set a limit of one year. If after one year, the account has not been used at all, then I want to delete the account and send an email to the last known email address informing the customer. How do other places handle this situation? Do you lock the accounts and then notify customers - then delete if no response in 2 weeks? What time limits are other people using? I see some people are doing 90 days of not logging in flags an account as 'dormant'.

LeRoy

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