Thank you, Greg, and good morning. Old Dominion's revenue for the third quarter of 2020 was $1.1 billion, which was a 0.9% increase from the prior year. We operated very efficiently during the quarter and established new company records for our operating ratio and overall profitability.
Our operating ratio improved 480 basis points to 74.5% and earnings per diluted share increased 24.8% to $1.71.
Our revenue growth for the third quarter may have been modest, but we were pleased to actually return to a positive trend. The increase reflects a 1.3% increase in LTL tonnage that was partially offset by the 0.6% decrease in LTL revenue per hundredweight. This yield metric as well as overall revenue was negatively affected by the significant decrease in the average price of diesel fuel as well as changes in the mix of our freight.
Our underlying pricing trends remained relatively consistent during the third quarter, as indicated by the continued strength in our LTL revenue per shipment. On a sequential basis, revenue per day for the third quarter increased 18.1% as compared to the second quarter of 2020, while LTL shipments per day increased 15.4%.
Following the steep drop in volumes in April that generally resulted from the initial state-at-home orders, our shipment levels have steadily increased above our normal sequential trend. At this point, in October, with almost a week remaining in the month, our revenue per day is trending higher by approximately 2% to 2.5% as compared to October 2019.
Our shipments per day trended in line with normal seasonality, but our weight per shipment is in the 1,570- to 1,600-pound range, which is lower than the third quarter.
While the weight per shipment is still higher on a year-over-year basis as compared to October 2019, the sequential decrease is due to measures we took to limit the number of heavier-weighted LTL shipments in our system as well as improving revenue trends with our smaller customer accounts that generally have a lower weight per shipment than a larger national account.
As usual, we will provide the actual revenue related details for October in our third quarter Form 10-Q.
Our third quarter operating ratio improved 480 basis points to 74.5%, with improvement in both our direct operating cost and overhead cost as a percent of revenue. We improved the efficiency of our operations and produced increases in our laden load average, P&D shipments per hour and platform shipments per hour when compared to the third quarter of 2019.
While we will continue to add drivers and platform employees during the fourth quarter, as Greg mentioned, we believe we can effectively balance our labor-to-revenue trend in line with the normal sequential change in this expense line item by continuing to focus on productivity.
We will also maintain our disciplined approach to control discretionary spending and make every effort to minimize cost inflation in other areas. Old Dominion's cash flow from operations totaled $170.2 million and $686.5 million for the third quarter and first 9 months of 2020, respectively, while capital expenditures were $46.3 million and $166.5 million for the same periods. We paid $17.6 million of cash dividends to our shareholders during the third quarter, and returned $360.3 million in total capital to shareholders during the first 9 months of the year.
For the year-to-date period, this total includes $306.8 million of share repurchases and $53.5 million in cash dividends. There were effectively no share repurchases made during the third quarter due to the 6-month accelerated share repurchase agreement we executed in May. We recorded the initial delivery of shares in the second quarter, and the remaining unsettled shares will be delivered in the fourth quarter.
Our effective tax rate for the third quarter of 2020 was 24.8% as compared to 24.9% in the third quarter of 2019.
Our rate in the third quarter benefited from certain discrete tax adjustments, and we currently expect our effective tax rate to be 25.9% for the fourth quarter of 2020. This concludes our prepared remarks this morning. Operator, we'll be happy to open the floor for questions at this time.