I am searching for a proxy for monthly GDP. The variable should be high correlated with GDP and available for most countries. 1980-2014 on a monthly basis would be nice.
Do you have any suggestions?
The UNSD's Joint Oil Data Initiative (JODI) contains oil production, export/import and consumption on a monthly basis for all the countries in the world since 2002. I have a tutorial here on using the dataset:
The UNSD also publishes annually a very comprehensive energy statistics yearbook for 215 countries (currently).
'The 2010 Energy Statistics Yearbook is the fifty-fourth issue in a series of annual compilations of internationally comparable statistics summarizing world energy trends. which commenced under the title World Energy Supplies in Selected Years, 1929-1950. Annual data for 215 countries and areas for the period 2007 to 2010 are presented on production, trade and consumption of energy for solid, liquid, and gaseous fuels, electricity, and heat. Per capita consumption series are also provided for all energy products. Graphs are included to illustrate historic trends and/or changes in composition of production and/or consumption of major energy products. Special tables of interest include: international trade tables for coal, crude petroleum and natural gas by partner countries; selected series of statistics on renewables and wastes; refinery distillation capacity; and a table on selected energy resources. "
For the US there is a firm that calculates something from monthly data that the quarterly Bureau of Economic Analysis (BEA) GDP data is also based on: http://www.macroadvisers.com/monthly-gdp/