What's RDM an how do I choose

If you meant RMD instead of RDM, that stands for Required Minimum Distribution.  

The term RMD is most commonly used with regard to IRA distributions, but it does also apply to employer-sponsored retirement plans as well.  

If you are over 70 1/2, then you are required to take an RMD from your Traditional IRA accounts.  Typically, your IRA custodian will notify you of the amount that must be taken out of the account each year to meet the RMD requirements.  

If you are receiving a distribution from an employer-sponsored retirement plan, then the administrator of that plan has taken the RMD into account and the amount you receive during the year will satisfy the requirement.  

To learn more, take a look at the following article:  What is an RMD?

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