Point in time calculation #2 - excel

Question

Incident number
Received date
Closed Date
Time taken to close
111
01 Jan 2021
01 Feb 2021
31
222
01 Jan 2021
07 Feb 2021
37
333
01 Jan 2021
444
01 Jan 2021
I wanted to calculate the average number of days an incidents have been open at a point in time. So using the example above lets say at the end of Feb 2021 you would look at
Received date has to be less then the metric date (the metric date in this case being Feb 2021)
Closed date has to be either greater then metric date or empty (if the closed date is empty then the calculation for time taken to close would be from the received date to the metric date)
Using the example above the first two incidents would not been included, however the last two would be and so the different between 01 Jan 2021 and 28th Feb 2021 is 58 , divide that number by 2 as that’s the number of incidents included in the calculation to give you an average of 58. Using the same example the calculation for Jan 2021 would be 31 days for each incident as no incident was closed by 31st Jan, so its (31*4) / 4. I would be repeating this for Jan – Dec 2020 and 2021

Answer 1

The encoding of an unclosed incident with a missing value will require a case of if statement to properly compute the days open metric on a given asof date.
Example:
The days open average is computed for a variety of asof dates stored in a data set.
data have;
call streaminit(2022);
do id = 1 to 10;
opened = '01jan2021'd + rand('integer', 60);
closed = opened + rand('integer', 90);
if rand('uniform') < 0.25 then call missing(closed);
output;
end;
format opened closed yymmdd10.;
run;
data asof;
do asof = '01jan2021'd to '01jun2021'd-1;
output;
end;
format asof yymmdd10.;
run;
proc sql;
create table averageDaysOpen_asof
as
select
asof
, mean (days_open) as days_open_avg format=6.2
, count(days_open) as id_count
from
( select asof
, opened
, closed
, case
when closed is not null and asof between opened and closed then asof-opened
when closed is null and asof > opened then asof-opened
else .
end as days_open
from asof
cross join have
)
group by asof
;
quit;