There will be major changes in the composition of global GDP
Global GDP is taken as sum of GDP for 34 OECD and 8 non-OECD G20 countries.
Source: Long-term Growth Scenarios, OECD Economics Department Working Paper No. 1000
In late 1980s, the situations were very different (Japan: 8~9%, China: 3~4%, India: 2~3%, etc.)
Looking to 2060: Long-term growth prospects for the world
OECD
http://www.oecd.org/eco/economicoutlookanalysisandforecasts/lookingto2060.htm
http://www.oecd-ilibrary.org/docserver/download/5k8zxpjsggf0.pdf?expires=1355243325&id=id&accname=guest&checksum=5EEC853C7504B2993B8A7B45AEE321EA
Written by Åsa Johansson, Yvan Guillemette, Fabrice Murtin under the supervision of David Turner and Giuseppe Nicoletti. Statistical analysis and modelling support was provided by Christine de la Maisonneuve, Guillaume Bousquet and Francesca Spinelli.