Hello, I would like to get such time series data of gdp components for 30 or so top countries. I wish the data to be free if possible and easily accessible.
Free data that are made consistent was being provided by Penn World Tables (PWT). Some old versions can be found on the web. Some universities have added some updated data to it--check with UC Davis. In addition, the US International Trade Councle (ITC) allows some download of trade data on their website. It is a big problem to make the data consistent. If you want to buy some consistent and current data, check the GTAP website.