Diff between course from Navigraph-maps and skyvector-maps

Hi Experts,

Just a quick question, have been wonder for a while why there sometimes are differentiated between the course between Navigraph-maps and skyvector-maps or will this have something to do with cycle / date or magnetic deviations :-). Just an example below but have seen this many places. (often just 1 or 2-3 degree in diff).

Like: Date 23/10-2022
Navigraph → LATINA 111.2 LAT 49 -à Z803 course says 097
Skyvector → LATINA 111.2 LAT 49 -à Z803 course says 096

Please advise

Appreciates any feedback or tips :slight_smile: , Thanks In Advanced

S. Olsen