New amendments of Charging Income tax on Tea business

Union budget 2009-10 has made some amendments for charging income tax on tea business. If you are doing tea business . Then , you have to deduct 10% depreciation on total sale proceed of tea. After this you can deduct other expenses. For income tax purpose , 60% of balanced amount is not chargeable to income tax .
We can explain it with example
Sale proceeds of tea business = Rs. 1000
less depreciation on sale proceed
(10% ) = Rs. 100
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balance = Rs. 900
less other expenses = Rs. 300
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balance = Rs. 600
less 60% of this balance = Rs. 360
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Income subject to charge under IT act = Rs. 240
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