Adolfo Castro Rivas -- Chief Executive Officer
Thank you, Cathy and good morning everybody. Thank you for joining us on our conference call to discuss our third quarter results.
Before entering into the discussion of our results for the quarter, let me make a brief comment about the potential Riviera Maya train. Over the past months, we have met on several occasions with the transition team of the new government that has presented this project, which includes an origination station at Cancun Airport. We will continue to work with them to establish the most effective way in which our Cancun Airport subsidiary can participate in the coordination of this project and it moves ahead in the construction of these train terminals.
Moving on our performance, our Mexican operation posted another quarter of solid results with a strong passenger traffic growth. Despite the higher cost base as we continue to ramp up terminal four open toward the close of last year, we show positive traffic growth in Puerto Rico this quarter, following the impact of Hurricane Maria last year. And improved overall dynamics in Colombia particularly a sharp pickup in domestic traffic following capacity adjustments at the leading carrier. More than 13.3 million passengers travel across over 16 airports during the third quarter, with total traffic picking up to almost 7% year-on-year, driven by growth in our three countries of operation.
In Mexico, traffic increased 6.7% year-on-year, reaching 8.3 million passengers. Domestic traffic rose almost 11%, while international traffic rose close to 3%. Growth was driven by a solid performance at Cancun and further supported by traffic growth across all of our airports. Traffic in Puerto Rico continues to recover up almost 4% to 2.2 million passengers, although total traffic remains impacted by airline capacity reduction following the effects of hurricane Maria last year.
Domestic traffic rose 5%, while international traffic continues to post negative comps down almost 6%. Colombia posted a strong recovery, up over 7% year-on-year, reaching 2.8 million passengers up from a 4% decline in prior quarter. Domestic traffic grows over 6%, while international traffic growth remaining stable at 12%. Looking ahead we expect traffic in Colombia to continue recovering gradually reaching normalized levels next year.
Moving on to our financial results. Remember that financials for the quarter reflect the full consolidation of our Puerto Rico operations in third 2017 and third quarter 2018 while we began consolidating Colombia starting October 19th last year. Consolidated revenues excluding constructions was over -- was up over 20% year-on-year to MXN3.7 billion, driven by positive contribution across all our operations. Revenues ex-construction increased 14% in Mexico and 9% in Puerto Rico, while Colombia contributed over MXN480 million. On a stand-alone basis, revenues ex-construction in Colombia increased 19% year-on-year. Aeronautical revenues remained strong, up 30% year-on-year, reaching MXN2.3 billion reflecting growth of almost 14% in Mexico, 4% in Puerto Rico. Colombia contributed with over MXN320 million in aeronautical revenues in the quarter, representing a 16% increase on a stand-alone basis.
We remained focused on driving growth in commercial revenues, which increased 25% year-on-year to MXN1.2 billion. Reflecting a robust performance across the board Mexico continues to post solid commercial revenue growth, up 15% as we continued to ramp-up operations of terminal four Cancun Airport. We are also pleased with 17% increase in commercial revenues achieved in Puerto Rico, while Colombia contributed with MXN100 million in commercial revenues. On a stand-alone basis, commercial revenues in Colombia, increased 28% year-on-year.
Commercial revenues per passenger fell to MXN92.5 this quarter from MXN99.5 in the same quarter last year, reflecting the consolidating effect. On a stand-alone basis however, we deliver another quarter with higher commercial revenues per passenger across our three countries of operation. Mexico posted a 7.6% increase in commercial revenues per passenger, reaching MXN108. This was mainly driven by the continued ramp up of terminal four at Cancun Airport and a strong performance of our retail operations. With terminal four basically completed and almost all commercial spaces rented, we are now focused on fine-tuning operations there to better understand passenger needs as we strive to maximize commercial revenues per passenger. We are also working with the concessionaires of Terminal two to adjust the offering for the new mix of passengers at these terminal.
Commercial revenues per passenger rose 13% in Puerto Rico to MXN108. Commercial revenues increased across all categories with growth mainly driven by strong performance in ground transportation, advertising, car rentals and parking lots. We believe that the construction efforts in the Island are driving a great part of these increase in the transportation related categories. Finally, Colombia reported a 20% increase reaching MXN35 per passenger as we continue to make headway in upgrading these operations. As you know, increasing commercial revenues is our main objective in Colombia. We expect to reestablish duty-free operations at Rionegro airport before year-end, which should continue to drive higher commercial revenues per passenger going forward.
Moving down the P&L, consolidated EBITDA increased 19% year-on-year with MXN2.3 billion mainly driven by a 12% increase in EBITDA in our Mexican operations and a contribution of MXN200.6 million from the consolidation of Colombia starting October last year. While results at our Puerto Rico operations are slowly improving, EBITDA at this operation declined 6% year-on-year still impacted by higher cost and expenses.
Consolidated adjusted EBITDA margin, which excludes the effects of IFRIC 12 with respect of the construction of or improvements to the concession assets in Mexico, Puerto Rico and Colombia was 63% in third quarter '18 compared with the 68% in third quarter '17 due to the consolidation effect. Regionally, on a stand-alone basis, adjusted EBITDA margin in Mexico declined by 122 basis points to 70% mainly impacted by the additional costs from the new terminal four as we continued to ramp up operations. As well as an average increase of 63% in the price per kilowatt hour compared with this same period of last year.
In Puerto Rico adjusted EBITDA margin declined to 48% from 56% in the same quarter of last year. This resulted mainly from a concession fee of MXN32 million this quarter, equal to 5% of revenues up from a fixed MXN2.5 million during the first five years of the concession. A 70% increase in the insurance cost along with a higher security expenses to meet authorities request also impacted adjusted EBITDA in Puerto Rico.
Adjusted EBITDA margin in Colombia in turn declined 360 basis points to 48% mainly impacted by higher cost of services resulted from the new areas we opened at the end of last year at Rionegro airport and concession fees originating from the increase in revenues. Note that our bottom line for the third quarter was impacted 125% year-on-year increase in depreciation and amortization. This was mainly driven by a higher depreciation in Colombia, resulting from an increased concession value and the new areas opened at Rionegro airport. And to a lower extent from the impact of IFRS 3 on the valuation of our investment in concessions in Colombia and Puerto Rico. Results for the quarter were also impacted by a higher consolidated comprehensive financial cost. Of MXN280 million compared to MXN103 million loss in the year ago quarter. This resulted mainly from a higher non-cash foreign exchange loss in the quarter to a lesser extent due to an increase in interest expenses.
Now turning to the balance sheet, we maintain a solid financial position with net debt down by MXN1.2 billion sequentially and a net debt to the last 12 months EBITDA ratio of 1.2 times. During the course of our nine months we made capital expenditures close to MXN1.4 billion. Of these over MXN640 million were invested in Puerto Rico and more than MXN390 million in Colombia. In addition, we also invested almost MXN330 million in Mexico, mainly in Cancun's terminal four and major maintenance works at the other eight airports.
In Puerto Rico we are taking care of major maintenance works like the change from asphalt to concrete in taxiway as well as making investments in connection with a reconstruction process following Hurricane Maria and the construction of a building for cargo activities. We estimate that total damages amount to approximately $60 million of which $50 million should be reimbursed by the insurance company. So we will see some temporary CapEx as we receive the reimbursements in. In Colombia we continue with the mandatory works like the cargo area expansion at Rionegro airport.
Grupo Aeroportuario del Sureste, SAB de CV (ASR) Q3 2018 Earnings Conference Call Transcript -- The Motley Fool
