SAS. calculate % from DISTINCT COUNT - sas

Question

I am working in SAS Studio Version: 2022.09.
I am working with survey data and will be tracking Region-Facility that has not submitted a survey in over 3 weeks. Surveys are voluntary but ideally facilities will submit a new survey weekly.
Region
Facility (Type&Name)
Date Survey Submitted
North
Hospital-Baptist Hospital
1/01/2023
South
PCP-Family Care
1/01/2023
North
PCP- Primary Medical
1/08/2023
South
PCP-Family Care
1/08/2023
North
Hospital-Baptist Hospital
1/15/2023
North
Hospital-St Mary Hospital
1/15/2023
West
Daycare-Early Learning
1/15/2023
West
Hospital-Methodist
1/15/2023
South
Daycare-Early Learning
1/15/2023
To obtain a list of facilities by region that submitted before but have not submitted in 3 weeks. Since we do not expect to be successful with every facility, we will stop following facilities after 10 weeks.
Data have;
set want;
DaysDiff=intck('day', Date, today());
run;
proc sort data=have;
by Facility Region Date;
run;
data have;
set have;
by Facility;
if last.Facility;
run;
proc sort data=have
out=SurveysMissing;
BY Region Facility;
WHERE DaysDiff>21 AND DaysDiff<70;
run;
To assist in determining significance of losing facilities that had not submitted recently, I would like to obtain a %.
[Total # of facilities per REGION that have not submitted survey >21 <70] / [Total # of facilities per REGION that have reported in the last 10 weeks]
/*#facilities not submitted >21 AND <70 /*
proc sql;
SELECT Count(Distinct Facility) AS Count, Region
FROM have
WHERE DaysDiff>21 AND DaysDiff <70
GROUP BY Region;
run;
/*Count of Distinct Facilities per Region*/
proc sql;
SELECT Count(Distinct Facility) AS Count, Region
FROM have
WHERE DaysDiff <70
GROUP BY Region;
run;
Would I need to create tables and do a left join to calculate %?
Thanks.

Answer 1

In Proc SQL a true condition resolves to 1 and false to 0. You can leverage this feature to compute the ratio of sums of expressions or binary flags.
Example:
Compute the ratio based on a subquery that flags facilities
proc sql;
create table want as
select
region, sum (isquiet_flag) / sum (submitted_flag) label = 'Fraction of quiet facilities'
from
( select region, facility
, min(today() - date_submitted ) > 21 as isquiet_flag
, min(today() - date_submitted ) < 70 as submitted_flag
from have
where today() - date_submitted < 70
group by region, facility
)
group by
region
;

Answer 2

In your last data step for have, add an indicator for missing survery.
data have;
set have;
by Facility;
if last. Facility;
surverymissing = (daysdiff > 21); * contains 1 if condition is true, otherwise 0;
run;
Then use proc summary to compute your numerator and denominator for each region. The numerator is the sum of surveymissing while the denominator is the count of the same.
proc summary data=have nway;
where daysdiff < 70;
class region;
var surveymissing;
output out=region_summary (drop=_:) sum=SurveysMissing n=TotalFacilities;
run;