These figures are a good finger in the air guide for construction only.
You would need to add in the planning and approval stages. You also need to factor in whether they are construction of additional rectors at existing sites (which a lot are that are included in those figures) as opposed to a new site from scratch.
The last 2 built from scratch in Korea where 8 and 10 years (first unit) This is also a country with considerable expertise in their construction.
Japan appears quicker. Though their latest plant from scratch(Oma), started construction in 2008 and is currently slated for start up in 2026
