The Home + Control App displays the consumption of your connected wired products. The power outlets, cable oulets, contactors and latching relays measure consumption with an accuracy of +/- 5%.
The consumption displayed for dimmers and light switches is an estimate based on the power of the bulb, that you can fill in the Home + Control App.
Go in the App settings,select the room and the switch, then fill in the "Power of the lightbulb" value.