Hadrontherapy Shallow Proton Beam

I am trying to validate simulated data from the advanced example Hadrontherapy. I am running the hadron_therapy.mac with 70MeV and 100,000 protons. The energy of the beam seems to be lower than it should be. I have made sure the range shifter and the modulator wheel are off. My Bragg peak is about 5mm shallower than it should be. Has anyone worked with Hadrontherapy? Does anyone know what the problem could be?

Here is my comparison of my 70MeV simulated beam in water vs experimental data of a 70MeV beam in water.

Have a look in DetectorConstruction and check the MeanExcitationEnergy for water. It should be 78 eV.

Which example (if any) is your code based on?