I am currently conducting a study regarding lifelong learning in EU member states. As part of this research, I analyze several indicators for the following time series: 2007, 2011 and 2013.
I have hit a roadblock with one of my indicators - Internet use activities (Individuals who used Internet, in the last 3 months, for training and education). The issue is that data is only available on Eurostat for the years 2011 and 2013, data for 2007 is missing for all EU member countries.
My question is if there is any way to estimate the missing data from 2007 based on the data available in 2011 and 2013, which has no missing values (my dilemma comes from the fact that I need to estimate past values, not predict future missing values).
For clarification, this is the data:
| GEO/TIME | 2007 | 2011 | 2013 |
|--------------------------------------------------|------|------|------|
| Austria | - | 3 | 3 |
| Belgium | - | 3 | 5 |
| Bulgaria | - | 2 | 2 |
| Cyprus | - | 2 | 3 |
| Czech Republic | - | 3 | 2 |
| Germany (until 1990 former territory of the FRG) | - | 5 | 5 |
| Denmark | - | 7 | 7 |
| Estonia | - | 5 | 5 |
| Greece | - | 4 | 4 |
| Spain | - | 10 | 10 |
| Finland | - | 12 | 13 |
| France | - | 4 | 5 |
| Croatia | - | 2 | 5 |
| Hungary | - | 5 | 4 |
| Ireland | - | 5 | 5 |
| Italy | - | 4 | 5 |
| Lithuania | - | 7 | 8 |
| Luxembourg | - | 6 | 9 |
| Latvia | - | 4 | 3 |
| Malta | - | 6 | 5 |
| Netherlands | - | 5 | 7 |
| Norway | - | 6 | 10 |
| Poland | - | 2 | 2 |
| Portugal | - | 3 | 2 |
| Romania | - | 4 | 3 |
| Sweden | - | 5 | 8 |
| Slovenia | - | 5 | 3 |
| Slovakia | - | 2 | 4 |
| United Kingdom | - | 6 | 9 |