Eurostat data contain detailed information on population and GDP evolution per country, as well as aggregated data on the EU27 level. These may be coupled with vehicle fleet data to calculate the various indicators.
For population data (Populationon 1 January by five years age group and sex): http://ec.europa.eu/eurostat/data/database
Data Navigation Tree -> Database by themes -> Population and social conditions -> Demography and migration (pop) -> Population (demo_pop) -> Populationon 1 January by five years age group and sex (demo_pjangroup)
Earth Resources Observation and Science (EROS) Center