Calculating kWh (using the simple formula given as an example in the forum) and finding drops in the chart, which makes no sense. I have verified that the additive is positive, yet I still see a pattern I cannot explain.

The formula is simple:

```
return my.value + (power.past(MINUTE,1).average/60);
```

But the result is unexpectedly jagged:

I expect this is due to the formula looking back too far for the previous (current) value, but I haven't had any luck calculating a better window. As an example, here is some of what I have been attempting:

```
var prev = my.lastValue(0);
var lastVal = (null === prev) ? my.value : prev.value;
return lastVal + (power.value/60);
```

FWIW, the data point is not set to update the context; instead, it's set to update every minute.

Any clarification is greatly appreciated.

Thanks,

Aldo