Nth business day of the month

[bibbnd]

I extracted some code(from SAS communities) to calculate the nth business day of the month. It is a little off.  I was testing the code to make sure it returned the 3rd day of the month. I noticed Jul ,Aug, and Oct were giving me the 4th day instead. All these months have 31 days so wondering if that is the reason. 

I want the 3 day of the month and will adjust for holidays for Jan, Jul and Sept only when it falls on a weekend.  Can anyone confirm what is happening in these months and maybe how to accommodate the 1 day difference.

Does SAS have a US holilday calendar?

data test;
format business_day1 business_day2 business_day3 business_day4 business_day5 date9.;

business_day1 = intnx('weekday', intnx('month', '23jun2024'd, 0, 'b'), 3);
business_day2 = intnx('weekday', intnx('month', '18jul2024'd, 0, 'b'), 3);
business_day3 = intnx('weekday', intnx('month', '06aug2024'd, 0, 'b'), 3);
business_day4 = intnx('weekday', intnx('month', '11sep2024'd, 0, 'b'), 3);
business_day5 = intnx('weekday', intnx('month', '25oct2024'd, 0, 'b'), 3);

run;

[SASKiwi]

INTNX WEEKDAY increments by business days, so you need to start on the last day of the previous month for your calculations to always work correctly. For example 1 Jul 2024 is a Monday and the first business day in the month. If you increment by three business days that is 4 Jul. Try this:

data test;
format business_day1 business_day2 business_day3 business_day4 business_day5 date9.;
business_day1 = intnx('weekday', intnx('month', '23jun2024'd, -1, 'E'), 3);
business_day2 = intnx('weekday', intnx('month', '18jul2024'd, -1, 'E'), 3);
business_day3 = intnx('weekday', intnx('month', '06aug2024'd, -1, 'E'), 3);
business_day4 = intnx('weekday', intnx('month', '11sep2024'd, -1, 'E'), 3);
business_day5 = intnx('weekday', intnx('month', '25oct2024'd, -1, 'E'), 3);
  put _All_;
run;