Clarity reg Calculation of Attrition Formula (Financial Broking firm where attrition at entry-level is very high)

Dear All, Will like to have clarity reg the proper calculation of the Attrition formula.
The Std formula that am aware of is :
Attrition% = No.of exits
.................................................. ............................................. * 100
( Opening Manpower Balance + Closing Manpower Balance ) / 2
Pls suggest if there is any other formula.
I am basically in a Financial Broking firm where attrition at entry-level is very high.

Dear Sanjay
Attrition% = No.of person left + No of person resigned
.................................................. ............................................. * 100
( Opening Manpower Balance + additional manpoer ( New recruit employees )
Example 2+2 / 58+6 *100 = Attrition% 6.35%
M. Jude
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