This is the device-wide count of data chunks sent that do not require in-order delivery. Unordered chunks are typically used for less sequence-sensitive traffic, so if this number climbs unexpectedly relative to the ordered count, it may indicate an application on this device using an SCTP stream in a way not originally intended for strict call sequencing. A spike here coinciding with a new application, such as bulk status polling, sharing an existing SCTP association would show up in this counter without affecting the ordered-chunk signaling stream.