Depreciation expense increased to $ 2,514,000 in the first nine months of 2021 from $ 2,289,000 in the first nine months of 2020, primarily due to capital additions related to the reopening of the Nashville Superspeedway .
The gain on the sale of land in 2021 and 2020 relates to the sale of approximately 350 and 97 acres of land to our Nashville plant, respectively.
The benefit for the conditional bond was $ 541,000 in the first nine months of 2021, compared to $ 112,000 in the first nine months of 2020. The benefit for 2021 was primarily from sales taxes collected. higher than expected to be allocated to the bond fund and used for debt service. The 2020 benefit came primarily from an increase in projected sales taxes to be collected as a result of our four-year sanction agreement with NASCAR for the Nashville Superspeedway and lower estimated interest rates on bonds.
Other income of $ 357,000 in the first nine months of 2021 represents pension benefits and equity gains. Other income of $ 115,000 in the first nine months of 2020 primarily represents pension benefits.
Our effective tax rates for the first nine months of 2021 and 2020 were 25.9% and 13.3%, respectively. The 2020 rate was reduced by the reversal of a portion of the valuation allowance for the state of Tennessee income tax assets.
Liquidity and capital resources
Our activities and cash flows from operating activities are seasonal in nature.
Free cash flow from operating activities amounted to $ 9,389,000 for the first nine months of 2021, compared to $ 8,440,000 for the first nine months of 2020. The increase in net cash provided in 2021 was primarily driven by higher operating income and the schedule of tax payments, partially offset by the schedule of payments related to the June 2021 NASCAR weekend.
Net cash flow from investing activities was $ 3,339,000 for the first nine months of 2021, compared to $ 5,404,000 for the first nine months of 2020. Capital expenditures of $ 10,489,000 during the first nine months of 2021 were primarily aimed at improving facilities related to the reopening of the Nashville Superspeedway. Capital expenditures of $ 545,000 in the first nine months of 2020 were primarily related to equipment purchases, property improvements and expenses related to the reopening of the Nashville Superspeedway. In May 2021, we completed the sale of approximately 350 acres of land at our Nashville Superspeedway facility for proceeds of $ 14,326,000, net of closing costs. The buyer had already paid us a deposit of $ 500,000 which was credited against the purchase price. In July 2020, we closed the sale of approximately 97 acres of land at our Nashville Superspeedway facility for $ 6,460,000, net of closing costs. The buyer had already paid us a deposit of $ 500,000 which was credited against the purchase price.
Net cash used in financing activities was $ 1,613,000 for the first nine months of 2021, compared to $ 94,000 for the first nine months of 2020. We paid $ 1,458,000 in cash dividends in June 2021. We purchased 51,791 and 50,572 shares of our outstanding common shares for $ 117,000 and $ 94,000 during the first nine months of 2021 and 2020, respectively, from employees in connection with the vesting of awards of restricted shares under our share-based incentive plan.
As of September 30, 2021, Dover Motorsports, Inc. and its wholly owned subsidiaries Dover International Speedway, Inc. and Nashville Speedway, USA, Inc., as co-borrowers, had a credit agreement of $ 25,000,000 with a banking group. On February 25, 2021, we amended the credit agreement: (1) to extend the maturity date to September 1, 2024; (2) reduce the total borrowings available under the facility from $ 30,000,000 to $ 25,000,000; and (3) replace the fixed charge coverage ratio with an interest coverage ratio. Interest is based on LIBOR plus a margin that varies between 125 and 175 basis points depending on the leverage ratio. As at September 30, 2021, there were no outstanding borrowings under the credit facility. The credit facility contains certain covenants, including a maximum ratio of funded debt to earnings before interest, taxes, depreciation and amortization (“leverage ratio”) and a minimum interest coverage ratio. Material adverse changes in our results of operations could affect our ability to maintain the financial ratios necessary to meet these requirements. In addition, the credit agreement includes a material adverse change clause. The credit facility also provides that if we default under any other loan agreement, that would constitute default under that facility. As of September 30, 2021, we were in compliance with the terms of the credit facility. The credit facility covers seasonal financing needs, capital improvements, letter of credit requirements and other general business objectives. After reviewing the outstanding stand-by letters of credit, the maximum remaining borrowings available under the credit facility were $ 13,612,000 as at September 30, 2021. We expect to be in compliance with the financial covenants and all other covenants. restrictive, for all valuation periods over the next twelve months.
On August 17, 2017, we entered into an agreement with an entity owned by Panattoni Development Company (the “Purchaser”) to sell approximately 147 acres of land in our Nashville plant for a purchase price of $ 35,000. the acre. On March 2, 2018, we closed the sale of the property with proceeds, less closing costs, of $ 4,945,000. The net after-tax proceeds were approximately $ 4,150,000, which resulted in a gain of $ 2,512,000. On September 1, 2017, we also granted the buyer a three-year option for approximately