Three Months Ended June 30, 2022 vs. Three Months Ended June 30, 2021
NOI for our Same-Store Community properties increased 14.7%, or $29.7 million, for the three months ended June 30, 2022 compared to the same period in 2021. The increase in property NOI was attributable to an 11.4%, or $33.7 million, increase in property rental income, partially offset by a 4.2%, or $4.0 million, increase in operating expenses. The increase in property rental income was primarily driven by an 8.5%, or $24.3 million, increase in rental rates, a $7.3 million decrease in rent concessions and a 12.5%, or $4.1 million, increase in reimbursement and ancillary and fee income, partially offset by a $1.4 million increase in occupancy loss. Weighted average physical occupancy stayed the same at 97.1% and total monthly income per occupied home increased by 11.4% to $2,134.
The increase in operating expenses was primarily driven by a 14.6%, or $2.4 million, increase in repair and maintenance expense due to the increased use of third party vendors as a result of an increase in the number of homes that turned as well as the impact of inflation on those third party vendor costs, a 26.6%, or $1.2 million, increase in insurance expense due to increased claims, and a 7.9%, or $0.9 million, increase in utilities, which was primarily due an increase in energy costs.
The operating margin (property net operating income divided by property rental income) was 70.2% and 68.2% for the three months ended June 30, 2022 and 2021, respectively.
Six Months Ended June 30, 2022 vs. Six Months Ended June 30, 2021
NOI for our Same-Store Community properties increased 14.4%, or $57.1 million, for the six months ended June 30, 2022 compared to the same period in 2021. The increase in property NOI was attributable to an 11.1%, or $65.0 million, increase in property rental income, partially offset by a 4.2%, or $7.8 million, increase in operating expenses. The increase in property rental income was primarily driven by a 6.9%, or $39.1 million, increase in rental rates, a $4.2 million decrease in our bad debt expense related to multifamily tenant lease receivables, a $13.0 million decrease in rent concessions, a $1.1 million decrease in occupancy loss and an 11.2%, or $7.1 million, increase in reimbursement and ancillary and fee income. Weighted average physical occupancy increased by 0.5% to 97.2% and total monthly income per occupied home increased by 10.6% to $2,350.
The increase in operating expenses was primarily driven by a 12.0%, or $3.8 million, increase in repair and maintenance expense due to the increased use of third party vendors as a result of an increase in the number of homes that turned as well as the impact of inflation on those third party vendor costs, a 31.9%, or $2.9 million, increase in insurance expense due to increased claims, and a 7.9%, or $1.9 million, increase in utilities, which was primarily due an increase in energy costs.
The operating margin (property net operating income divided by property rental income) was 69.9% and 67.9% for the six months ended June 30, 2022 and 2021, 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 June 30, 2022 vs. Three Months Ended June 30, 2021
The remaining 8.8%, or $22.4 million, of our total NOI during the three months ended June 30, 2022 was generated from our Non-Mature Communities/Other. NOI from Non-Mature Communities/Other increased by 262.0%, or $16.2 million, for the three months ended June 30, 2022 as compared to the same period in 2021. The increase was primarily attributable to a $15.8 million increase in stabilized, non-mature communities NOI due to operating communities acquired in 2022 and 2021, partially offset by a $1.3 million decrease in sold and held for disposition communities.
Six Months Ended June 30, 2022 vs. Six Months Ended June 30, 2021
The remaining 8.8%, or $44.1 million, of our total NOI during the six months ended June 30, 2022 was generated from our Non-Mature Communities/Other. NOI from Non-Mature Communities/Other increased by 255.0%, or $31.7 million,