Therefore to get more gasoline and drill more oil wells, some existing gasoline must be used up in the process, or internally consumed. This occurrence exists in every industry to varying extents resulting in a massive structure of interlining and constantly changing relationships between all industries. Further, if production in one industry changes, this change effects all other industries in one way or another due to inter linking relationships and internal consumption. On top of these complex internal relations exists a tendency of change relating to substitute and complementary goods effecting related markets and further entangling the complex relationship between industries of a large economy.
