Hi
You need to do it on 01.01.2014 either through LSMW or MM02 or T code MASS
If you are on ECC version of SAP, system automatically restores the Std price same as prevailing MAP and changes the Price control.. If you are on older versions, you need to manually make the Std price same as MAP from MR21 or MM02 and then change the price control
Br, Ajay M