The energy consumption of an S-Pedelec per km is the sum of all influencing factors during a ride. The amount of energy drawn from the battery is measured and divided by the kilometers ridden. See also in this chapter the topic 'General‚.
Evaluation from forums
In forums and Facebook groups, screenshots of Stromers are posted again and again showing the Omni driving statistics. I have used the total kilometers driven and average energy values for the evaluation. This results in a picture that also provides a statistical average across seasons and individual driving profiles. The statistics are also based on 60 screenshots and show the following:

While energy consumption develops linearly in terms of total kilometers driven, the more electric drivers drive, the faster they seem to travel.
The question remains: "Is there a correlation between energy consumption and speed?" The answer is yes, and is clearly shown in the diagram.

The Electricbikereview forum has published a somewhat older table on the consumption and range of Stromer S-Pedelecs. Here to go to the corresponding post.
Own experience
With my ST2 & ST3, I have noted the figures from the Omni's driving statistics for 4 years. These are not the 100% truth either, but they do provide an estimate. About 85% of the statistics come from commuting, the rest were leisurely touring trips.
To summarize: The energy consumption depends largely on the riding style, the cadence, the route profiles ridden, the settings of the torque sensor in the Omni and ultimately also on the Stromer being ridden. If you ride 'all in' and always at the possible speed limit, consumption can rise towards 18 Wh/km. If you take it easy and lower the average speed below 30 km/h, single-digit Wh/km are also possible.
> See also the topic here: 'General'