On my power graph. the red line is the CT, the green line is from counting meter revs. I use an average of the voltage either side of the mid point, I found it gave more convincing readings than a peak, especially when the peak is a spike. I multiply my figure by 7. It tends to be high when I'm not using much and low when somebody turns on a heavy appliance (Kettle, Tumble Drier, Shower etc etc). The problem with meter rev counting is that at very low usage it only gets an update every few minutes. It usually drops to sub 50W overnight between fridge and freezer and it takes 8 minutes to rotate at 50W. The graph just cribs the last reading when it hasn't had an update in the previous minute.