Components Considered For Calculating HRA In India

I badly need advise on calculation of my HRA. Below are the components of my salary besides my PF and PT. Please advise which components should I consider for the computation of HRA.
BASIC
HRA
CONVEYANCE ALLOWANCE
MOBILE ALLOWANCE
GRADE ALLOWANCE
SPECIAL ALLOWANCE
LOCAL CONVEYANCE
OTHER ALLOWANCE
HARDSHIP ALLOWANCE
Since I have no dearness allowance as listed in my salary breakup and I live in Mumbai, I want to know that from the remaining components which should I consider for the computation of HRA.

I think it is only Basic that you have to consider..
As mumbai is one of Metros so the Rule is that..
HRA should be 50% of basic wages...
Hope it will help you..
Yogendra.

HI,
You should take only Basic for computation of HRA as per Income Tax Act
rgds
vishwanath