Variable Portion cal for Shift wise Dep

Hi,

Could any body tell me how to calculate variable portion for calculation of Shiftwise Depreciation. For Ex I am giving the following Dep Rates.

Normal Dep (4.75% )

shift factor - 1

variable portion = 56.21052632

for double shift (7.42%)

shift factor - 2

variable portion - 56.21052632

for triple shift (10.34%)

shift factor - 3

variable portion - 58.21052632

Our Friend told to calculate variable portion as follows:

Variable portion=Diff between Two Dep Rates as per shift*100/Lower rate of Dep

I tried for Shift 2 and I am getting 56.21052632.

+Now my problem is while calculating for shift 3 using above formula I am not geting 58.2152632. Could any body tell me how to calculate shift 3 Variable portion.+

Thanks in advance.

Best Regards

Raj