I noticed that the calibrated upstream and downstream BCM charge did not match with each other. Talked with Pengjia, and we checked the BCM signal in scaler and HAPPEX, all of them show a systematic difference: down stream BCM charge is ~5% larger than upstream BCM charge (calibrated value). We found that this happened right after we moved to 1.1GeV. During 1.7GeV setting, upstream and downstream BCM charges are same. We do not know the reason yet. The Gain of BCM has not been changed. Pengjia suggests that we should do another Tungsten Calorimeter calibration. However, we still need to understand this problem.