Dietz Method

Hi Guys,

Just want some clarification on when to use Dietz or Modified Dietz.

My understanding is that you Dietz methods do not conform with GIPS unless proven it has an immaterial difference

is this correct?

thanks

For periods prior to 1 January 2005, cash flows can be assumed to occur at the midpoint of the measurement period. The Original Dietz method reflects this midpoint assumption. A time-weighted total return calculation that adjusts for daily weighted cash flows is required for periods beginning on or after 1 January 2005. Modified Dietz method.

https://www.cfainstitute.org/learning/products/publications/contributed/performance/Documents/gips_overview_lawton.pdf

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