It is up to you, I wouldn't taper it off because right when you are done with the letro you will be starting PCT and bumping the nolva up to 20mg which should stop any gyno from occuring and the nolva will also help to lower the estrogen that the letro might cause from the rebound effect. Some people taper it off because they feel that if they gradually lower the dose then they won't get any estrogen rebound effect.