The following code is used to calculate when Easter Sunday falls in any given year. This is especially handy in the Financial Services areas where certain jobs/processes are required not to be run on bank holidays.

 
%macro calculate_easter(year);
	%global easter;
	data _null_;
		a = mod(&year.,19);
 		b = floor(&year./100);
 		c = mod(&year.,100);
		d = floor(b/4);
		e = mod(b,4);
		f = floor((b+8)/25);
		g = floor((b-f+1)/3);
		h = mod(((19*a) + b - d - g + 15),30);
		i = floor(c/4);
		k = mod(c,4);
		l = mod((32 + (2*e) + (2*i) - h - k),7);
		m = floor((a + (11*h) + (22*l))/451); 
		n = floor((h + l - (7*m) + 114)/31);
		o = mod ((h + l - (7*m) + 114),31);
		easter = put(mdy(n,(o + 1),&year.),ddmmyy10.);
		call symput("easter",easter);
	run;

%mend calculate_easter;
%calculate_easter(year=2006);
%put ⩮