SCCM Monthly Software Update compliance report by osd365

Over the year’s I’ve worked with clients who express the following concerns.

We only get compliance of 93% to 95%. Our goal of reaching 99.9% compliance has never happened.
There is always a delta of machines that appear with a status of UNKNOWN.
We are not clear if the deltas we see each month are the same subset of devices or different.
When disabled, withdrawn, or superseded updates get removed from the Sofware Update Groups, the compliance data for those updates for the previous months get lost.
The current default ‘compliance’ reports within SCCM SQL reporting services do not show a monthly break down of software updates.