Mace is executed though measures have zero popcount

Hi,

I need to understand the why a mace expression is executing though related measures popcount is zero and it's taking time abopout 7 seconds as well.

<I 2017Dec21 14:21:30.023> Calculating PAMeanDevCumOptParp = tssum(PAMeanDevOptParp ,first ,current )

<D 2017Dec21 14:21:30.023> EvalLoopHelper::initIter (pameandevcumoptparp%1)

<D 2017Dec21 14:21:30.023> EvalLoopHelper::initIter (pameandevoptparp%1)

<D 2017Dec21 14:21:30.023> Initializing expression iterator "pameandevoptparp%1": priority 0

<D 2017Dec21 14:21:30.023>   0.% populated (0 / 174099926 cells); navalue = [0.]; dimension space: DimSpace(day:1463, itpt:2587, str:46, info:1)

<D 2017Dec21 14:21:30.023> EvalLoopHelper::initIter (LogicalSliceIterator(FULL, all cells))

<D 2017Dec21 14:21:30.023> Initializing expression iterator "LogicalSliceIterator(FULL, all cells)": priority 0

<D 2017Dec21 14:21:30.023> ............

<D 2017Dec21 14:21:37.920> 119002 vectors evaluated.

<P 2017Dec21 14:21:37.920>

<P 2017Dec21 14:21:37.920> =========================================================

<P 2017Dec21 14:21:37.920> TSI:3          0.000175      seconds for Expression::evalPostProcess

<P 2017Dec21 14:21:37.920> =========================================================