该INTNX
函数将计算一个递增的日期值,并允许指定生成的间隔对齐(在您的情况下是 n 个月的“结束”)
data have;
format date_of_last_repricing end_date date9.;
informat date_of_last_repricing end_date date9.;
* use 12. to read the raw date values in the datalines;
input repricing_frequency date_of_last_repricing: 12. end_date: 12.;
datalines;
3 15399 21367
10 12265 21367
15 13879 21367
;
run;
data want;
set have;
status = 'Original';
output;
* increment and iterate;
date_of_last_repricing = intnx('month',
date_of_last_repricing, repricing_frequency, 'end'
);
do while (date_of_last_repricing <= end_date);
status = 'Computed';
output;
date_of_last_repricing = intnx('month',
date_of_last_repricing, repricing_frequency, 'end'
);
end;
run;
如果您只想计算最近的结束日期,例如通过重新定价频率进行迭代时,您不必进行迭代。您可以将月份除以频率,以获得可能发生的迭代次数。
data want2;
set have;
nearest_end_month = intnx('month', end_date, 0, 'end');
if nearest_end_month > end_date then nearest_end_month = intnx('month', nearest_end_month, -1, 'end');
months_apart = intck('month', date_of_last_repricing, nearest_end_month);
iterations_apart = floor(months_apart / repricing_frequency);
iteration_months = iterations_apart * repricing_frequency;
nearest_end_date = intnx('month', date_of_last_repricing, iteration_months, 'end');
format nearest: date9.;
run;
proc sql;
select id, max(date_of_last_repricing) as nearest_end_date format=date9. from want group by id;
select id, nearest_end_date from want2;
quit;