Subtract Months and Add Days Formula

Hello,

Is there a way to 2 things in this formula(Add_Duration)? Below is the formula which works perfect but I will like to subtract -15 months and add +1 day to the selected date.

For example:
selected date is 6/20/2021, result wanted (after subtract -15 months and add +1 day to the selected date) = 3/21/2020. Thank you in advance for any help you may be able to provide.

IF(IS_EMPTY(pageVars.pickedDate), “No ETS Date Picked Yet”, "ROW Date: " + FORMAT_DATETIME_LOCAL(DATETIME(ADD_DURATION(pageVars.pickedDate, -15, “months”)), “YYYY-MM-DD”))