DPC Rate is the rate at which deferred procedure calls (DPCs) were added to the processors DPC queues between the timer ticks ...

DPC Rate is the rate at which deferred procedure calls (DPCs) were added to the processors DPC queues between the timer ticks of the processor clock. DPCs are interrupts that run at alower priority than standard interrupts.  Each processor has its own DPC queue. This counter measures the rate that DPCs were added to the queue, not the number of DPCs in the queue. This counter displays the last observed value only; it is not an average.