First of all, those Kaisaniemi normals have been been there for years, from several different sources. Don't you think they are more informative than only records from a 30-year period? Almost all other climate boxes have all-time records.

Secondly, the Helsinki-Vantaa sunshine stats were correct. Now when you changed them, they show Kouvola Utti's sunshine. Page 68, column 301 https://helda.helsinki.fi/bitstream/handle/10138/35880/Tilastoja_Suomen_ilmastosta_1981_2010.pdf

Thirdly, there is no annual mean temp classifying which is a subarctic climate and which not. In the Köppen qualification the requirements are 3 or less months with a mean temp of over 10C and the coldest month below -3C. https://en.wikipedia.org/wiki/Subarctic_climate
Winnipeg has a annual mean of 3C, and it's nowhere near the subarctic classification, as it too has 5 months with a mean temp above 10C
https://en.wikipedia.org/wiki/Winnipeg#Climate

Your percent possible sunshine calculations are totally wrong. Helsinki has on the 16th of July roughly 18 hours of daylight, some 540 hours. You have put 280 hours in the July box. 280/540 = 52%. You claim 75%. As you can see, Winnipeg has 400 hours of more sunshine annually, and it has 50.6% possible sunshine.

Please revert the to the data and discard your changes, as they are wrong, and have only done harm.