The minimum NAV method is backwards compatible (that is, this option does not change the returns you were calculating with previous versions).
To use this calculation method, select the Begin NAV method option when you set up a Dynamic Mutual Fund Returns field. The Minimum NAV method is the default. If you edit a Dynamic Mutual Fund Returns field that was created using a prior version, the option remains defaulted to use the Minimum NAV method unless you change it. 
Here is an example of how the CDSC Load Method option works:
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Finally, the load-adjusted return using the new option to use the begin NAV is -8.313%. In this example, the beginning NAV is higher than the ending NAV, so the load dollars are higher, and the return (-8.313%) is then lower than in the previous example. To calculate this return in PACE, set the load adjustment option on and use the Minimum NAV method.
To troubleshoot return calculations, edit or view the Dynamic Mutual Fund Returns field to see the parameters used to calculate the load dollars, as well as the other parameters.