Uh, okay...
32*100xe6 = 3,200,000,000 bps
that is the raw transfer rate, you will have to subtract the protocol from that, which is dependent on whether or not you have a single cycle, burst, or a mix of transfer types on the bus.
You will have to calculate the percentage of a transfer that is actually the data.
E.g. if a transfer takes 10 clock cycles and you only transfer 1 32-bit word then you have only 1/10 the bandwidth used for transferring your data so your effective bandwidth on the bus is going to be 320,000,000 bps.