It is of course hard to find ideal test cases because nearly any country you seek to compare over some time period there are major events happening which dwarfs anything to do with tax rate.
What you can do is look at the decade from 1950 to 1960 which is when Nordic generally had lower or equal tax rates to the US. Then you can look at 1960s to 1970s where tax rates in Nordics got a lot higher.
I have looked at this and not really seen any clear difference. Once you get into the late 1970s you get oil crisis which affects everybody to a different degree.
I do a lot of my graphs with Our World in Data. Awesome site for anyone who wants to geek out with statistics:
I also at times use Makie plotting library with the Julia programming language. I download data from IMF, Our world in Data, World Bank, SSB (Norwegian statistical bureau) and various places like that. They tend to have datasets in CSV files you can use.
No I am not retired. I do primarily focus on writing now, but I am doing a lot of work on a Julia Programming book. I got sick of doing programming full time and wanted to focus more on writing. I realized I am probably more in love with writing than programming. Maybe the fact that my mom is a journalist had some effect on me.
Yeah it can be a lot of work to write, but at times it has been terapeutic for me. Like I might not be able to get around to doing anything else which SHOULD be done, but I can get myself to sit down and write. Writing can be fun and you can forget about a lot of other problems.
But writing on demand on specific topics can be really hard. It only works for me because I write stuff I feel like writing there and then.