The World Bank provides time series data for many countries on Information Technology in its database, the World Development Indicators (WDI). The Bank has also developed a Digital Adoption Index available at http://www.worldbank.org/en/publication/wdr2016/Digital-Adoption-Index
United Nations -- Data on the information technology indicators related to the Millennium Development Goals is available at http://unstats.un.org/unsd/mi/mi_goals.asp .
Gapminder -- Gapminder is an innovative data presentation web site which provides dynamic views of data changes over time using bubble graphs. Graphs are available for economic, population, health (including HIV/AIDS), environmental, agricultural and information technology data. Raw data can be downloaded from the site and a desktop version of the software is available free. Users can customize graphs using existing data, but cannot add new data. Much of the data used is from the World Bank and UN organizations. Gapminder is at http://www.gapminder.org .
International Telecommunications Union (ITU) --The ITU makes available data in spreadsheet format on fixed-telephone, mobile-cellular and broadband subscriptions as well as historical communications data in .pdf files. This data is available at https://www.itu.int/en/ITU-D/Statistics/Pages/stat/default.aspx