Spotlight's battery consumption not displayed in list of Apps under Battery

When we click Settings>Battery, we are able to see the section Battery Usage under which a list of Apps consuming battery power is shown. The list of Apps also displays the activity On Screen as well as in the Background. It also shows the battery power consumption by each App as a percentage of the total consumption. However, the list of Apps shown does not include Spotlight and other iOS processes which are great power hogs. It is known that after every iOS update there is a surge in battery drain on that iPhone for a few days, which is normally attributed to the indexing activity by Spotlight and other background iOS processes. Hence, the list of Apps in the Battery usage monitoring should also include Spotlight and other iOS processes to reflect the true efficiency of iOS.