How to filter/Tag Outlier values

msacs09

We have a single table that captures daily sales and loans and we wanted to filter all loans.. so generally our loans will be quite high compared to actual sales ex:- sale value is ~38877and loan is ~1073173 and we wanted to filter all loans 

sample data

date   dept_id  Sal
    201907   10     723
    201907   10     1073173
    201907   10     38877
    201907   10     100000
    201907   10     500000
    201908   20     16818
    201908   20     701
    201908   20     700
    201908   20     850000
    201908   20     1000000
    201909   10     5909999
    201909   10     19999997
    201909   10     21999998

Expected Output as below

    Y    date   dept_id  Sal     out_of_normal_values
    201907   10     723         N<br>    201907   10     1073173     Y<br>    201907   10     38877       N<br>    201907   10     100000      Y   
    201907   10     500000      Y
    201908   20     16818       N <br>    201908   20     701         N<br>    201908   20     700         N
    201908   20     850000      Y
    201908   20     1000000     Y
    201909   10     5909999     Y<br>    201909   10     19999997    Y<br>    201909   10     21999998

msacs09

date dept_id Sal out_of_normal_values 201907 10 723 N 201907 10 1073173 Y 201907 10 38877 N 201907 10 100000 Y 201907 10 500000 Y 201908 20 16818 Y 201908 20 701 N 201908 20 700 N 201908 20 850000 Y 201908 20 1000000 Y 201909 10 5909999 Y 201909 10 19999997 Y 201909 10 21999998 Y