Thanks, Joe. Good morning, everyone, and thank you again for joining us today. I'll provide more details on our third quarter 2020 adjusted financials, provide an update on our cash flow and liquidity, and conclude with a high level view of our expectations for the fourth quarter and some preliminary thoughts on our 2021 sales. I'll start with our third quarter results, which as expected were meaningfully impacted by the COVID-19 pandemic.
Sales decreased by 22% to $236 million. Adjusted operating income decreased 57% to $25 million, and adjusted EBITDA decreased 47%. We reported $17 million of adjusted net income, a decrease of 58%, and adjusted earnings per diluted share declines of $0.50. Though the profitability of the third quarter reflected the rapid decline in volume together with our decision to continue executing our strategy and maintaining the infrastructure to support the return of sales post COVID, it was improved over the second quarter.
Consistent with our prior communication, the second quarter saw our lowest level of profitability. Following the third quarter, our focus on manufacturing excellence improved our ability to adjust favorable costs to lower sales volume and better manage the challenges of operating with social distancing. We are confident that having maintained strategic and often long-term investments throughout the pandemic, our customers and the patients we ultimately serve will benefit.
Turning to the next slide. We see the graphical representation of the impact of 22% year-over-year reduction in sales had on our income. While improved over the second quarter, our balanced approach to cost management during a temporary but steep reduction in sales is seen in the operational drivers column and contributes a $29 million reduction in our adjusted net income in the third quarter versus last year. Our continued focus on debt and interest rate management as well as lower LIBOR reduced our interest expense by $2 million and contributed $0.07 per share of growth.
The impact from our effective tax rate was significant in the third quarter and contributed $5 million of year-over-year income growth. We benefited from discrete items recorded in the third quarter related to the favorable impact of final tax reform regulation, the benefit of our tax planning strategy of optimizing foreign tax credits and R&D tax credits on our 2019 return exceeding our original provision. This resulted in a negative 15% adjusted effective tax rate in the third quarter and 11% for the third quarter year-to-date.
We expect our total year 2020 adjusted effective tax rate to be between 12% and 14%, which will likely increase in 2021 back to 2019 levels without the significant benefits and discrete items seen this year. And finally, foreign exchange was unfavorable $1 million in the third quarter, primarily related to the euro.
I'll now transition to providing an update on our third quarter cash flow and continued financial strength as our liquidity continue to increase. In the third quarter, we continued the strong conversion of income to cash and generated $32 million in cash flow from operating activities and $24 million in free cash flow despite the impact of COVID on our sales. We reduced our net total debt, which is our total debt minus cash on hand, by $23 million. We continue to steadily reduce our net total debt consistent with our strategy.
However, our debt leverage ratio increased to 3.5x adjusted EBITDA as our trailing 4-quarter adjusted EBITDA is lower given the impact of the COVID-19 pandemic on the second and third quarter. In addition to the strength of our operational cash generation, I am pleased to share that following a patent litigation judgment being affirmed by the United States courts of appeal in Integer's favor, we received $28 million of cash early in the fourth quarter on October 15. The following day, we repaid our outstanding debt by an equal amount and our net total debt reduced to $719 million, down from $770 million at the end of the second quarter. Despite the pandemic, we have reduced our net total debt this year by over $90 million.
In the context of the cash generation and debt payments we just discussed, the next slide provides a holistic view of our financial strength we have maintained during the pandemic. As mentioned earlier, we increased our liquidity again in the third quarter. At quarter close, we had $100 million in cash on hand with $243 million in total liquidity, up $13 million from the second quarter. During the quarter, we paid down $120 million on our revolver as the liquidity markets have remained stable. This is consistent with our expectation to pay the revolver by year-end. With the patent judgment cash receipt, our liquidity increased an additional $28 million in the beginning of the fourth quarter.
We continue to manage our working capital, and we expect to continue generating positive cash flows for the remainder of 2020. We believe we have ample EBITDA cushion on our leverage and interest coverage covenants, and we continue to meaningfully reduce our debt. Integer has not only proven its ability to withstand the challenges of the pandemic, but to also maintain critical investments to execute the company's strategy and make Integer stronger.
I'd now like to give you additional detail and context on the fourth quarter outlook that Joe summarized in the opening slide. First, you may recall earlier this year, we suspended our financial guidance due to the significant uncertainty created by the COVID-19 pandemic. We remain in the midst of the pandemic, and we still see considerable uncertainty, and therefore, we are not resuming full financial guidance. However, in keeping with our commitment to provide as much clarity and transparency as possible, we want to provide more insight into our fourth quarter expectations.
Our backlog has improved, which gives us confidence in our expectation of fourth quarter sales being between $255 million and $270 million. We expect the fourth quarter to be the beginning of the sales recovery for Integer due to the industry inventory build in the first half of 2020 and its depletion in the second half. This anticipated sequential improvement of $20 million to $35 million in sales from the third to fourth quarter is in line with our prior communication. We expect adjusted operating income margin rates to recover as volume recovers, which is also consistent with our prior communications. In fact, we expect the fourth quarter adjusted operating income margins to be 200 to 300 basis points higher than the third quarter.
As it relates to the fourth quarter, sales still being down 17% to 22% versus prior year, I'd like to draw your attention to 2 items that fall outside of the recovery of the medical device industry. As compared to the prior year, the fourth quarter of 2020 has 5% fewer days and it is also impacted by the downturn in the energy market and in turn on our Electrochem sales. Excluding these differences, we are getting closer to converging with the medical device industry as our customers deplete the inventory they built in the first half of the year when our sales growth outpaced the industry. Joe will discuss this dynamic in greater detail when he provides a COVID-19 update in the next section.
We've heard a lot of conversation in the industry and for a lot of investors ask us how to think about 2021 from a growth rate perspective. It's the best comparison for 2021 against the COVID impacted 2020? Or should we compare 2021 against 2019? So we have thought about this, and we have begun to build our 2021 budget for planning purposes. We started to look at what 2021 will look like, assuming it was the exact same volume -- unit volumes at 2019. What's the same and what's different. There were 4 items that jumped out to us that would yield a different dollar amount of sales in 2021, even with the same unit volume in 2019.
The first 2 items were the same headwinds we discussed when we shared our 2020 pre-COVID outlook in February, and they still apply in the comparison to 2019. The first one is Nuvectra. We are very clear about the impact of Nuvectra's bankruptcy in the fourth quarter of 2019 when we spoke about our 2020 outlook. We had $17 million of sales in 2019 that would not repeat in 2020, and nor will it repeat in 2021. So when compared to 2019, this becomes the first adjustment for our comparable 2021 baseline.
The second item relates to fewer calendar days versus 2019 that we also discussed when we shared our pre-COVID 2020 outlook. This creates approximately $10 million of headwinds. The third item is the contraction of the energy market in 2020 due to excess supply in oil, coupled with the reduced demand from the pandemic. This impacts our nonmedical business, Electrochem, which we expect to be approximately $23 million down in 2020 sales versus 2019. Though we cannot make the claim that we know exactly how the energy markets will look in 2021, it is our operating assumption that there will be no recovery in the energy market or in our Electrochem sales until 2022. So again, this creates an additional adjustment to our 2021 baseline as we compare to 2019.
And last, we know that we give 1% to 2% of price reductions to our customers every year. These are built into our long-term supply agreements, which cover roughly 2/3 of our sales to customers. So we have to consider that in 2021 on the same exact production and shipment unit volume in 2019. The cumulative reduction in selling prices for 2 years will reduce our sales approximately $38 million in 2021. The sum of these 4 items yields $1,170,000,000 as comparable 2021 versus 2019. As we continue our budget process, we will apply our industry growth rate assumptions as a starting point against this $1,170,000,000. In February, we expect to share our guidance using this framework.
With that, I'll turn the call back to Joe. Thank you.