A foundation year is explicitly requested on our questionnaires and updating forms. However, when we decided to tackle this study, only 64% of the organizations had registered one. Therefore we initiated an updating campaign specifically targeted at the database entries without registered foundation year. Additionally and whenever possible, we visited the web sites of the organizations who maintained one and/or issued e-messages requesting explicitly those foundation years. This had a very beneficial impact as the proportion of available foundation years increased to 86%, i.e. 4371 foundation years for a total of 5065 effective database entries (i.e. excluding the cross-references).
(*) All ranges end in 1998, except the "publishers'' one where no foundation year more recent than 1995 has been registered.
(**) A value lower than the size of the corresponding sample indicates that some duplications of entries for the same organizations (at different locations, but with the same foundation year) have counted only for one occurrence (see text).
The geographical distributions of the corresponding organizations are illustrated in Figs. 1 to 3 (World, Europe, North America). They are consistent with the distributions in the previous studies. Thus we believe that a study based on such an amount (and such a percentage of the database contents) can lead to quite significant results.
|Figure 3: StarGuides/StarWorlds' organizations with a registered foundation year - North American blowup|
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