Although there are not many of these sources, they are a valuable reference for comparisons. Some articles are based on time series, i.e. annual national information is compiled over a long period of time and in accordance with Community nomenclature. These data are very common at Eurostat, which is responsible for collecting the official figures drawn up by each country, bringing them into line with the common nomenclature and calculating the various aggregates. The amount of information is even greater than that of the blanket sources. However, this information is collected using varying methods and concepts.
Time series are excellent databases capable of serving as a basis for discussion in the long term.
In view of their shorter processing time, they are available sooner and detail recent events. The advantage of such sources is that they provide an accurate response to questions asked. The results of surveys are sometimes different from those of time series.