Date Calculation Issue with Subtracting a Large Number of Years

[YOUNGmaxer]

Describe the bug
I've encountered an issue with dayjs when subtracting a large number of years from a date. Specifically, when I attempt to subtract 129 years from a date, the resulting date is incorrect.

Expected behavior
The date after subtracting 129 years should accurately reflect the original month and day, not resetting to the first day of the month.

Information

• Day.js Version v1.11.12
• OS: Mac OS
• Browser Chrome/129.0.0.0
• Time zone: America/Toronto

[isaiah2004]

hey i think this is because of the way 1 y maybe defined as 365 days. or the Definition of the term year itself. what is your expected behaviour?

[YOUNGmaxer]

Expected behaviour：
dayjs().tz('America/Toronto').format('YYYY-MM-DD') // '2024-10-17'
dayjs().tz('America/Toronto').subtract(129, 'y').format('YYYY-MM-DD') // '1895-10-17'