Create quarter as per month

[subrat1]

I want to create a macro. I have one column : month (from 2000 to 2015Q4 = 16 years * 4 quarters * 3 months per quarter = 192 months

plus 2016Q1,2016Q2 = 6 months

So as per my month column i want to create Quarter Column using macro as my month will keep increasing my quarter shoud increase.

for example:

Month	Quarter
4	6
5	6
6	6
1	3
2	3
3	3
7	9
8	9
9	9
13	15
14	15
15	15
10	12
11	12
12	12
16	18
17	18
18	18
43	45
44	45
45	45
119	120
118	120
120	120
60	60
58	60
57	60
89	90
88	90
90	90
180	180
178	180
179	180
191	192
192	192
190	192

[Reeza]

Your logic isn't clear. Please clarify your question. 

[ballardw]

It looks like your "quarter" variable is last "month" of a group of three. Correct?

[subrat1]

Yes quarter is last month of group of three

[Ksharp]

Assuming I understand what you mean, and there is no gap in MONTH.

data have;
infile cards expandtabs;
input Month;
cards;
4	6
5	6
6	6
1	3
2	3
3	3
7	9
8	9
9	9
13	15
14	15
15	15
10	12
11	12
12	12
16	18
17	18
18	18
43	45
44	45
45	45
119	120
118	120
120	120
60	60
58	60
57	60
89	90
88	90
90	90
180	180
178	180
179	180
191	192
192	192
190
;
run;
data have;
 set have;
 if mod(_n_,3)=1 then group+1;
run;

proc sql;
select *,max(month) as Quarter
 from have
  group by group;
quit;

[Astounding]

Another possibility:

data want;

do _n_=1 to 3 until (done1);

   set have end=done1;

   quarter = max(month, quarter);

end;

do _n_=1 to 3 until (done2);

   set have end=done2;

   output;

end;

run;

The UNTIL conditions are possibly overkill ... they allow for the possibility that you only have 1 or 2 months in the last group, rather than 3 months.

[Reeza]

Quarter = floor((month + 3)/3)*3;

[Astounding]

Reeza,

I'm not so sure that will work for the largest month of the three, but it gives rise to some interesting ideas.  This variation should work:

quarter = ceil(month/3) * 3;

[Reeza]

True...or change to 2.5 in addition.

floor(month+2.5)