This read-only INTEGER (0..38330) reports the current transmit cell rate, truncated to whole cells per second, that the IMA group actually provides in the transmit direction considering only the links currently in the Active state, per the documented formula N times link rate times (M-1)/M times (2048/2049), where M is the IMA frame length. An administrator watches this to see the real bonded throughput available right now, which drops if a member link goes inactive, as opposed to the nominal capacity implied by the total configured link count. For example, the MIB documents that with M=128 and 8 active T1 lines the rate works out to about 28728 cells/sec, so a reading noticeably below that on an otherwise 8-line T1 IMA group would indicate fewer than 8 links are currently active.