Thank you. Good morning, everyone. We are here to present the results from second quarter 2018. In the period, we saw a continued recovery of demand for PCs in Brazil. The market grew by 12% year-on-year. Positivo Tecnologia supported the market performance with a 35% growth in the same period. The growth occurred in all the segments. In the retail, we registered 22% growth year-on-year, 57% in government, 52% in the corporate segment.
Because of that, our market share increased by 3 percentage points in Brazil, reaching 18%. In the mobile phone market, the highly competitive environment continued. We saw the sales concentrated in the three major manufacturers. Our margins were impacted by the U.S. dollar appreciation, and we are passing through the price, this increase, but in the second quarter, it was not enough to protect the margins.
Our net debt closed the quarter in BRL 200 million. It is 14% down. Our Hi Technologies received an investment of BRL 15 million from Monashees and Qualcomm Ventures. Going to page number four. Here we have some color on the market scenario. The PC segment in Brazil grew by 12% in the quarter. We can see that since 2016, the market has been growing 5% between Q2 2016 to Q2 2018, and 12% this quarter compared to second quarter 2017. Our market share, which is 18%, this is the highest level in two years. You can see the graph on the left side below. In mobile phones, the market grew by 7%.
The three largest manufacturers, you can see in the graph below, they have 82% of the total market. The room for other manufacturers is only 18%, so it is very tight. Our market share was 2.6% in the quarter. If we compare it one year ago, it was 4%. Going to page five. Here you can see the impact on costs that damaged our profitability. You can see here in the first graph, the exchange rate close to BRL 4. It came [inaudible] . Because we had some headache to mitigate these impacts, we had to pass this to price in the second quarter. It was not enough.
We can see that our sales margin dropped to 4.6%, coming from 10% one year ago. Hello. Sorry, guys. We have a terrible connection. Coming back to page four, here we can have some color on the market scenario. For computers, as you can see in the first graph, the trend is very favorable. The market is growing since 2016. You can see that in second quarter 2018, we had 1.4 million units sold in Brazil. It is a double digit growth, so it is very healthy sales in the country.
Positivo sold more and we did more and we are getting an increasing market share, which is 18% in the second quarter, 3 percentage points more than the market share we had in second quarter 2017. In mobile phones, the market also grew with 7.7%, but here we have the issue of the highly competitive environment with the three largest manufacturers concentrating 82% of the total market. If we compare this one year ago, it was only 74%. Because of that, our market share contracted to 2.6% in the period. If we compare it one year ago, Positivo had 4% in second quarter 2017.
On page five, here you can see the impact in the profitability from the increase in the cost. The first and more important is the exchange rate. The Brazilian currency devaluated a lot since the end of the first quarter. You can see that the FX was close BRL 4 for each dollar, and we had to pass this to price, but it was not enough in the period to protect the margins. Also, we have a strong increase in the memory card price. This is a phenomenon happening in other world. Price has doubled from 2016 on. This affects mainly the sales that requires this advance, such as the government bid.
You can see that the sales margin dropped to 4.6%, mainly because the impact from the FX and also in the case of the government, the memory card price. We believe that in the end of the third quarter, the first two supplies from the industry through the sales channel will be concluded. We expect a margin rebound in the second half 2018. On page six, we have more detail on the prevention that Hi Technologies was involved.
This company received an investment of BRL 15 million. The major holders are Monashees and Qualcomm Ventures. They have together 32% of the company. Also, we created an option pool representing 7.5% of the capital of this company, focusing in future share-based compensation plans. We think that this capital injection is going to be very helpful for Hi Technologies, and they will have more strength to bear with this expansion. Moving to page eight. Here we have some figures in the volume. You can see that the Positivo sales were very healthy growth in all the segments.
Retail 8%, government 55%, corporate 58%. When we analyze per brand, we can see that Positivo grew by 35% and compensated with reduction of 29% i n Argentina, with Positivo BGH . Mobile phones. We reduced the volumes in the smartphone segment that compensated with feature phones. If we analyze the both together, the volume will be flat year-on-year. On page nine. The net revenue reaches BRL 485 million. It was 12% up year-on-year. Again, we can see the growth in the retail and the government.
In the corporate segment, we have a reduction of 32%, mainly caused by a project that we had in the last year related to set-top boxes, and it was very strong volume in the first half 2017. This year we have the project, but not so big. That's why the revenue in the segment is reduced. If you analyze all the groups, as I mentioned, it was growing a lot in the corporate also. Average prices, you can see that they are basically flat from the first quarter to the second quarter. We did expect that the prices will increase in the quarter. We can see this happen in the third quarter.
We should see, in the end of this year, the margin recovering. Moving to page 10. We can see the COGS and the sales expenses. COGS was higher due to the U.S. dollar appreciation, reaching 76.9%. Sales expenses also increased 15%. This time because of the after-sales, which increased from 2.9%- 5.6%, mainly caused by the higher compensation of government revenue this year. Also, we have a provision for a client in the other one in sales expenses. We had BRL 8 million of provision for clients this quarter.
G&A expenses was flat year-on-year, when you consider the recurring line, which is personal and labor expenses. In the quarter was 22% up, mainly because of the higher expenditures in R&D. Page 11. The operational results is that BRL 8 million EBITDA with a margin of 1.6%. We reported a net loss of BRL 11 million. In the [first connected result] we have an improvement, both because of the exchange variation that we made a profit of BRL 4 million. Also the cost of debt was reduced from BRL 17 million- BRL 11 million.
This is because of the reduction of interest rates in Brazil and also the lower cash position that we are carrying and less loans from banks. We will have a better cost of debt this year. Moving to page 12. The details of working capital. We closed the quarter with BRL 375 million in working capital. Net debt reduced by BRL 30 million, reaching BRL 270 million. That's it. Thank you so much for your attention. I am open for Q&A session.
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