Nine Months Ended September 30, 2024 vs. Nine Months Ended September 30, 2023
NOI for our Same-Store Community properties increased 1.4%, or $10.6 million, for the nine months ended September 30, 2024 compared to the same period in 2023. The increase in property NOI was attributable to a 2.3%, or $25.8 million, increase in property rental income, partially offset by a 4.4%, or $15.2 million, increase in operating expenses. The increase in property rental income was primarily driven by a 1.6%, or $17.2 million, increase in rental rates, and a 7.7%, or $9.5 million, increase in reimbursement and ancillary and fee income. Weighted average physical occupancy increased by 0.1% to 96.7% and total monthly income per occupied home increased by 2.1% to $2,554.
The increase in operating expenses was primarily driven by a 12.9%, or $5.9 million, increase in personnel costs primarily due to a refundable payroll tax credit related to the Employee Retention Credit program in 2023, a 4.9%, or $3.4 million, increase in repair and maintenance expense due to an increase in the cost per home of those that were turned during the year, the impact of inflation on third party vendor costs and weather-related events, a 2.2%, or $3.1 million, increase in real estate taxes due to higher assessed valuations and a 11.5%, or $2.6 million, increase in administration and marketing.
The operating margin (property net operating income divided by property rental income) was 68.9% and 69.5% for the nine months ended September 30, 2024 and 2023, respectively.
Non-Mature Communities/Other
UDR’s Non-Mature Communities/Other represent those communities that do not meet the criteria to be included in Same-Store Communities, which include communities recently developed or acquired, redevelopment properties, sold or held for disposition properties, and non-apartment components of mixed use properties.
Three Months Ended September 30, 2024 vs. Three Months Ended September 30, 2023
The remaining 5.0%, or $14.2 million, of our total NOI during the three months ended September 30, 2024 was generated from our Non-Mature Communities/Other. NOI from Non-Mature Communities/Other increased by 35.0%, or $3.7 million, for the three months ended September 30, 2024 as compared to the same period in 2023. The increase was primarily attributable to an $5.0 million increase in stabilized, non-mature communities NOI due to development communities completed and communities acquired in 2023 becoming stabilized, partially offset by a $2.7 million decrease in sold and held for disposition communities NOI due to the sale of an operating community during the nine months ended September 30, 2024 and the partial sale of four operating communities in 2023.
Nine Months Ended September 30, 2024 vs. Nine Months Ended September 30, 2023
The remaining 6.4%, or $54.2 million, of our total NOI during the nine months ended September 30, 2024 was generated from our Non-Mature Communities/Other. NOI from Non-Mature Communities/Other increased by 13.2%, or $6.3 million, for the nine months ended September 30, 2024 as compared to the same period in 2023. The increase was primarily attributable to a $22.6 million increase in stabilized, non-mature communities NOI due to development communities completed and communities acquired in 2023 becoming stabilized and a $4.1 million increase in non-residential/other NOI primarily due to higher retail tenant rents partially offset by a $20.8 million decrease in sold and held for disposition communities NOI due to the sale of an operating community during the nine months ended September 30, 2024 and the partial sale of four operating communities in 2023.
Gain/(loss) on sale of real estate owned
For the nine months ended September 30, 2024, the Company recognized gain/(loss) on sale of real estate owned of $16.9 million as compared to $325.9 million on sale of real estate owned for the nine months ended September 30, 2023. The decrease in 2024 as compared to 2023 was attributable to the sale of an operating community located in Arlington, Virginia during the nine months ended September 30, 2024, as compared to the partial sale of four operating communities located in various markets during the nine months ended September 30, 2023.
Interest income and other income/(expense), net
For the three months ended September 30, 2024 and 2023, the Company recognized interest income and other income/(expense), net of $6.2 million and $(3.1) million, respectively. The increase in 2024 as compared to 2023 was primarily