ALV Control and Screen Processing

I am using an ALV control for data entry for a custom application in 4.6C. I have a field outside of the control on the same screen that is a weighted average of some of the data in the ALV control. When the user changes the data in the ALV I then recalculate the weighted average and attempt to display the new value on the screen. The variable holding the weighted average has the correct value but the user sees the initial value until they put the cursor somewhere on the screen, not in ALV, and hit enter. I have tried the dynp_values_update and the dynp_update_fields function modules but neither seemed to push this value to the screen. Is there a way to simulate the enter on the screen or am I doing something wrong? Please help.

Thanks in advance!

Mike