Please note that this post links to websites that are in Spanish, if that's a problem, please do NOT click on the links!
It is now just over two years since the WT send the now infamous 17 September 2014 letter regarding the programme of building Kingdom Halls to all congregations in Spain. (letter page one / letter page two)
This week, as the WT released their annual 2017 Yearbook, it was revealed that Spain had the 21st highest increase of publishers from last year.
But, despite this increase in publishers, it is notable that in Spain the number of congregations continues it's downward spiral - from a peak two years ago during the 2014 Service Year of 1,545, down 43 to 1,502 congregations in the 2016 Service Year.
And the result of that now infamous letter - read out in all the congregations in Spain two years ago?
Out of the 705 Kingdom Halls in Spain two years ago - they are now apparently down to 650.... this still, though, places the WT as the 4th largest religion is Spain, by places of worship - in fact some 9.6% of ALL places of worship in Spain are Kingdom Halls (assumng that each Catholic Parish has just the one registered place of worship).
The Observatorio del Pluralismo Religioso en España's Data Exploitation for December 2016 has an interesting summary of the various religions in Spain - including the number of registered places of worship each one has - though it should be noted that it is unclear exactly how they've counted them (vis-a-vis multi-auditoriums and evening/weekend rented halls)
For those interested, they also provide a dataset/map that shows the location of each place of worship, by religion