Nine Months Ended September 30, 2021 Compared to Nine Months Ended September 30, 2020
Revenues. Our revenues increased by $512,386 (101.2%), for the nine months ended September 30, 2021 compared to the nine months ended September 30, 2020, from $506,526 to $1,018,912, which was primarily related to an increase of $496,328 in our commission and other brokerage income, which increased as a result of increased revenues from existing home sales caused by home-buying trends in our markets.
In 2020, and, in particular, the second quarter of 2020, we experienced a severe decline in closed sales volume in New York City. Therefore, as a result of the impact of the COVID-19 pandemic on the New York City market, and combined with the increased demand for existing-homes in other areas of the U.S., the percentage of our brokerage revenues from the New York City market declined from approximately 46% in 2019 to approximately 32% for the twelve months ended September 30, 2021.
In particular, the New York City market continued to improve in the second and third quarters of 2021. For the nine months ended September 30, 2021, the percentage of our brokerage revenues from the New York City market increased from 30.8% from the comparable 2020 period to 34.1%. The nine months ended September 30, 2021 demonstrated continued strength in the residential real estate market, which has improved markedly from a sharp decline in transactions, primarily in the second quarter of 2020, due to factors related to the COVID-19 pandemic. As our markets began reopening and vaccines for COVID-19 have become available, and consistent with home buying trends in the U.S., our business improved significantly in markets complementary to New York City, including South Florida (Miami and Palm Beach), the New York City suburbs (Long Island, Westchester County and Connecticut), the Hamptons, Los Angeles, and Aspen. More recently, we have experienced a recover in New York City as well. For the nine months ended September 30, 2021, our commission and other brokerage income generated from the sales of existing homes increased by $176,130 in the Southeast region, $164,466 in New York City, $66,359 in the West region, and $57,120 in the Northeast region, which excludes New York City, in each case compared to the comparable 2020 period. In addition, our revenues from Development Marketing increased by $32,253 for the nine months ended September 30, 2021.
Operating Expenses
Our operating expenses in 2020 and 2021 were significantly impacted by the COVID-19 pandemic in 2020 and, beginning in the second half of 2020, home buying trends. In the second quarter of 2020, in response to the COVID-19 pandemic, we made operating adjustments that resulted in reduced expenses and, in 2021, home-buying trends, which began in the second half of 2020, resulted in significantly increased demand for existing homes and, thus, an increase in associated expenses. As our business improved with market re-opening, beginning in the fourth quarter of 2020, we relinquished certain expense-reduction initiatives implemented during 2020. In addition, the increases in business also resulted in increased personnel expenses (associated with both discretionary compensation as well as the reinstatement of salary levels) and advertising expenses (associated with increased listing volume) in the 2021 period.
Real Estate Agent Commissions. As a result of our growth in commissions and other brokerage income, our real estate agent commissions expense increased from $351,325 for the nine months ended September 30, 2020 to $737,767, or $386,442 (110%). Real estate agent commissions expense, as a percentage of revenues, increased from 69.4% in the 2020 period to 72.4% in the 2021 period as a result of a higher percentage of revenues being generated in the Southeast (Florida) and Western (primarily California) regions, which traditionally pay higher commission rates than other regions.
Sales and Marketing. Sales and marketing expense increased from $40,649 for the nine months ended September 30, 2020 to $59,331 in the comparable 2021 period. The increase was the result of increased demand for our active listings in 2021 (caused by home buying trends and reopened markets after the COVID-19 pandemic) as well as significant growth in revenues associated with increased demand for existing homes in our markets in 2021.
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