Note: This article is part of Morningstar's January 2015 5-Point Retirement Portfolio Checkup special report.
Whether your retirement portfolio consists of dozens of holdings or just a few, from time to time, it's a good idea to assess how each is performing and to take a look under the hood. That's why it's important to know which performance benchmarks and key metrics to use when sizing up each holding individually. In doing so, you should look at both past performance and forward-looking measures designed to provide guidance as to how the investment will perform moving forward. That way, you can determine whether things in your portfolio are humming along just fine, a few upgrades are in order, or wholesale changes need to be made.