It's not supporting what you claimed. It's too shallow.
I'll just go the theist route then: It's evidence. You may not like it, or even accept it, but it's evidence.
Theism has increased after a decline in the last century.
And this has what to do with a current decline? Are you going to claim to know the future (something you have distinctly admonished me against) and state that there
will be increase later? That would be interesting.
Atheism has decreased after huge jump with the communist movement which is correspondence data.
Back on the atheism kick I see. Are you sure you know what we're discussing in this thread?
Importance of religion is a whole different ball game. That does not provide insight into growth or decline in theism or anti theism. For this you have to get into age groups, historical data to compare in retrospect to see at 18-29 they don't think religion is important, but when they grow they think it's more important, are becoming stupid after the age of 29 or do they have other reasons?
In the end, "we'll see" is all either of us is going to be able to say. Seems to me I am the one more easily able to say it. So here goes. We'll see.
A quantitative study like that needs much further analysis and one will have to go to the build up of the hypothesis which would have been an initial qualitative study in order to understand it better.
I don't know... some of the questions are pretty darn simplistic. Such that delving so much further into the impetus behind the study doesn't seem very necessary to me. If someone could construe the question in various ways, and without knowledge of what the research is after some context is missing, that's one thing. but in the study I snagged that data from, we're talking about very simple questions that cannot easily be misinterpretted, and don't really require any prerequisites.