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The main graph shows the power consumption graph for the selected time period. The selected period is shown as main graph curve, with a previous period added for comparison. The comparison “shadow” will for all* time periods be the selected time period starting before the main time period meaning that if you choose Last week it will compared with the week before. If you choose Last 4 weeks it will compare with the 4 weeks before that.
* Only exception is Yesterday that will compare with the same weekday the week before.
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