Other logistics services net revenues, which include transportation management services, customs, warehousing, and small parcel, increased 37.0 percent in the fourth quarter of 2012. Excluding Phoenix, we estimate that other logistics services net revenues increased approximately 15 percent in the fourth quarter of 2012. This was primarily due to transaction increases in our transportation management and customs services.
Sourcing net revenues increased 11.3 percent in the fourth quarter of 2012. This was due to increased net revenue margin.
Our payment services net revenues decreased 67.6 percent in the fourth quarter of 2012 due to the T-Chek divestiture. We have recorded a gain of $281.6 million related to this divestiture in the fourth quarter.
For the fourth quarter, operating expenses increased 35.6 percent to $311.0 million in 2012 from $229.4 million in 2011. This was due to an increase of 37.8 percent in personnel expense and an increase of 30.0 percent in other selling, general, and administrative expenses. For the fourth quarter, operating expenses as a percentage of net revenues increased to 70.0 percent in 2012 from 57.2 percent in 2011. During the fourth quarter of 2012, operating expenses grew faster than net revenues due to the increased performance-based stock vesting expense as a result of the sale of T-Chek.Excluding certain non-recurring items from acquisitions and divestitures, adjusted operating expenses increased 16.5 percent in the fourth quarter of 2012 compared to the fourth quarter of 2011. This includes an increase in adjusted personnel expenses of 16.7 percent and an increase in adjusted selling, general and administrative expenses of 16.1 percent. During the fourth quarter of 2012, adjusted operating expenses grew faster than net revenues primarily as a result of the acquisition of Phoenix. Phoenix has a higher operating expense to net revenue ratio than C.H. Robinson. Our adjusted personnel expense increase was driven by an increase in our average headcount of approximately 20 percent, partially offset by declines in various incentive plans that are designed to keep expenses variable based on growth in earnings. Adjusted other operating expense growth was driven primarily by an increase in amortization of intangible assets acquired, travel, and warehouse expenses.