Sorting portfolios based on criteria (top30%,Middle 40%. and Bottom 30%)

[Myura]

Currently, I have the following table
Company---------Date--------Exchange-------Size
A-------------------2000----------------A-------------50
A-------------------2001----------------A------------ 100
B-------------------2000----------------B------------450
B-------------------2001----------------B------------- 458

I want to allocate each company into three categories

"Top" ==> Top 30%
"Middle" ==> Middle 40%
"Bottom" ==> Bottom 30%

Calculating cutoff values should be filtered with 'year' and 'Exchange'=A
I have tried the following formula

<code style="margin: 0px; padding: 0px; border: 0px; font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace, sans-serif; white-space: inherit;"> =if([B/M]>PERCENTILEX.INC(FILTER(June,June[exchg]="A"&&EARLIER([datadate])=[datadate]),June[B/M],0.3),"L",IF([B/M]>PERCENTILEX.INC(FILTER(June,June[exchg]="A"&&EARLIER([datadate])=[datadate]),June[B/M],0.7),"M","T"))

</code>For some reasons, It is not working as it should be.

Thanks in advance.