Because average annual real GDP growth rates are so low.
Between 1929 and 1945, average annual real GDP grew at a compound annual rate of 4.74%.
Between 2007 and 2023, average annual real GDP grew at a compound annual rate of 1.82%, which is under-performing the sixteen year Great Depression and WWII era rate by almost 62%.
Up until 2007, the country averaged 3.44% from 1929.
Something remains rotten in Denmark.
