PCR to clear temporary variables created

Hi,

I am looking for help on Opeartion in Time Management to clear the temporary variables created during evaluation.

Ex:

*

****

HRS=10.001

ADDVSKITF

So KITF variable will have 10.001 and so on till the calculation goes on.

How can I clear those temporary variables to zero values.Which operation do I use.

ZVR2 * ****

ZERO=&KITF

ZERO=&HYJ

This doesnt help...there is no operation with the name ZERO in SAP.

Appreciate your help.