Downstream operations, which now also includes the chemicals business, generates a third of Shell's profits worldwide and is known for its global network of more than 40,000 petrol stations and its 47 oil refineries. The downstream business, which in some countries also included oil refining, generally included a retail petrol station network, lubricants manufacture and marketing, industrial fuel and lubricants sales and a host of other product/market sectors such as LPG and bitumen. The practice in Shell was that these businesses were essentially local and that they were best managed by local "operating companies" – often with middle and senior management reinforced by expatriates. In the 1990s, this paradigm began to change, and the independence of operating companies around the world was gradually reduced. Today, virtually all of Shell's operations in various businesses are much more directly managed from London and The Hague. The autonomy of "operating companies" has been largely removed, as more "global businesses" have been created.
When did Shell switch to treating businesses as local, independent companies?