Monthly adjustment number (1 is one, four and five), (2 is two, six and seven), (0 is three) (3 is eight), (4 is nine and ten) and (5 is eleven and twelve).
However, in leap years, that is, January and February, 1 must be subtracted to calculate the number of branches.
Example: 1999 April16 (99× 5+99 ÷ 4+9+16+30+1) ÷ 60 = 9+35, corresponding to "one hundred days".
If it exceeds 2000, use 100 as the multiplier. For example, 20 14, with 1 14 as the multiplier.