Working days from 2025-12-06 to 2025-12-27 (no holidays):
  2025-12-08 (Mon) - format(w)=1
  2025-12-09 (Tue) - format(w)=2
  2025-12-10 (Wed) - format(w)=3
  2025-12-11 (Thu) - format(w)=4
  2025-12-12 (Fri) - format(w)=5
  2025-12-15 (Mon) - format(w)=1
  2025-12-16 (Tue) - format(w)=2
  2025-12-17 (Wed) - format(w)=3
  2025-12-18 (Thu) - format(w)=4
  2025-12-19 (Fri) - format(w)=5
  2025-12-22 (Mon) - format(w)=1
  2025-12-23 (Tue) - format(w)=2
  2025-12-24 (Wed) - format(w)=3
  2025-12-25 (Thu) - format(w)=4
  2025-12-26 (Fri) - format(w)=5

Total: 15 days