I don't actually know whether contributions, conversions and earning are considered per account or in aggregate, but if you are over age 59-1/2, and because your first Roth account was opened more than 5 years ago, it doesn't matter. All your withdrawals are tax-free. Specifically,
- Withdrawal of contributions is always tax-free
- Withdrawals of conversions is free from regular income tax, but may be subject to a 10% penalty if you are under age 59-1/2
- Withdrawal of earnings is subject to income tax if the account is less than 5 years old or you are under age 59-1/2, and a 10% penalty if you are under age 59-1/2.
