create a calculated column to segment selected data based on 20/80 percent split

[DanJBay1978]

Hi

Can anyone one assist with helping me understand how a can create a calculated column that segments the data selected into top 20% vs bottom 80% split of the selected data. Using the below example of 50 records - when ranked highest to lowest -flag the top 20 % (10 records) as "top20percent" and the remaining records as "bottom80Percent".

Thanks in advance.

Reference	Days	Flag
215640009	171	Top20Percent
204643040	163	Top20Percent
201134031	160	Top20Percent
205662022	156	Top20Percent
201661023	147	Top20Percent
205140074	147	Top20Percent
203205017	133	Top20Percent
201620002	122	Top20Percent
201695012	114	Top20Percent
201193038	107	Top20Percent
215611018	107	Bottom80Percent
201134008	100	Bottom80Percent
201699105	99	Bottom80Percent
205140065	99	Bottom80Percent
205140047	95	Bottom80Percent
201693013	94	Bottom80Percent
215611027	93	Bottom80Percent
205140049	89	Bottom80Percent
205635007	88	Bottom80Percent
205662023	87	Bottom80Percent
201100036	86	Bottom80Percent
202198110	85	Bottom80Percent
201134027	84	Bottom80Percent
201661009	80	Bottom80Percent
205140076	78	Bottom80Percent
201191047	77	Bottom80Percent
201663014	77	Bottom80Percent
201100034	76	Bottom80Percent
203205020	74	Bottom80Percent
201134002	69	Bottom80Percent
203198072	69	Bottom80Percent
205122027	63	Bottom80Percent
205140036	60	Bottom80Percent
201100053	59	Bottom80Percent
215653001	49	Bottom80Percent
215105003	46	Bottom80Percent
205662018	43	Bottom80Percent
201134016	37	Bottom80Percent
201134029	36	Bottom80Percent
201134033	35	Bottom80Percent
201629003	35	Bottom80Percent
214108018	35	Bottom80Percent
201699040	32	Bottom80Percent
203109010	32	Bottom80Percent
205140023	31	Bottom80Percent
203110005	29	Bottom80Percent
215690007	25	Bottom80Percent
201689027	21	Bottom80Percent
215611062	21	Bottom80Percent
215690012	14	Bottom80Percent

[Zubair_Muhammad]

@DanJBay1978

Try this calculated column

MyFlag_ =
VAR myref = [Reference]
VAR rowcount =
    COUNTROWS ( Table1 )
VAR Top20rows =
    SELECTCOLUMNS (
        TOPN ( INT ( rowcount * .2 ), Table1, [Days], DESC, [Reference], ASC ),
        "Ref", [Reference]
    )
RETURN
    IF ( myref IN Top20rows, "Top20 Percent", "Bottom80Percent" )

[Zubair_Muhammad · Accepted solution]

@DanJBay1978

File attached as well