Vermont’s Moving Target. How a Housing Number Grew Seven Times in Three Years
The methodology behind the math.
alexsys.substack.com · Part VIII · By Alexsys Thompson · April 2026
What This Piece Found
► The 40,000-home figure originated in a January 2023 VHFA blog post. This series has not located any publicly documented independent verification before it was embedded in statute.
► The same VHFA researcher produced a figure seven times smaller in 2020 — same agency, same planning cycle, same methodology base.
► Three new components were added between 2020 and 2023. Two of them — vacancy normalization and pandemic-era demand — VHFA flagged with question marks in its own legislative presentation.
► The IRS migration data shows the pandemic surge that anchored the upper scenario had already reversed before the projection was published.
► The vacancy target — 5% — is a national benchmark. Vermont’s long-term owner vacancy average was 1.3%. The gap between those two numbers accounts for 11,023 units in the projection.
► Act 181 passed in June 2024. Two months later, the same agency revised the figure downward. This series has not located any public reconciliation of that revision with the number already in statute.
There is a number at the center of Vermont’s housing debate that most Vermonters have heard but few have examined.
Forty thousand homes by 2030.
It appears in Act 181’s justification framework. It appears in the Let’s Build Homes coalition letter signed by legislators, employers, and advocacy organizations. It appears in DHCD press releases, regional planning documents, and legislative testimony. Senator Anne Watson cited a figure derived from it at an Act 181 press conference this year. The series documented that in Part VII.
What the number’s public appearances do not include is an explanation of where it came from, what assumptions produced it, or why the same agency produced a figure seven times smaller three years earlier.
This piece examines that record.
Every claim is sourced to a primary document or confirmed public record. Open questions are labeled open. The reader assesses what the pattern means — the series does not tell them.
The Number Everyone Knows
On January 25, 2023, Vermont Housing Finance Agency Research and Community Relations Director Leslie Black-Plumeau published a blog post on the VHFA website. The title: “30,000–40,000 More Vermont Homes Needed by 2030.”
It moved fast. Within weeks it was in legislative testimony. Within months it anchored the HOME Act of 2023. The following year it was the justification framework for Act 181. By January 2025 it was the organizing principle of the pro-housing advocacy apparatus at the Statehouse.
Here’s what that number looked like across the documents it traveled through:
The range across all five documents runs from 24,000 to 41,185 — a gap of more than 17,000 homes. Nobody reconciled these figures publicly.
This series could not locate a side-by-side methodology comparison in the public record. So we built one.
To understand how a range that wide is even possible, you have to go back to where the number started — and what it used to be.
Where It Started: 5,800
Three years before the 40,000 figure appeared, the same agency published a very different number.
The 2020 Vermont Housing Needs Assessment — the federally required five-year report VHFA produces for DHCD — put the number at about 5,800 primary homes needed by 2025.
Same agency. Same lead researcher. One-seventh the number.
The 2020 methodology followed a straightforward trajectory. Household projections purchased from Claritas LLC showed near-flat growth at 0.18% annually — meaning Vermont was projected to form 2,353 new households statewide between 2020 and 2025, with 89% of that growth concentrated in Chittenden County. Most of the rest of Vermont was projected to lose households. There was no vacancy normalization component, no pandemic-era demand scenario, no housing loss replacement component.
Household formation is the demand side of the equation. Housing stock — the total number of physical dwelling units — is the supply side. In Vermont, both had been declining for forty years. The rate at which new homes were being added to the state’s housing stock had dropped every decade since the 1980s:
That was the trajectory. That was the baseline. That was 5,800.
Source: 2020 Vermont Housing Needs Assessment, VHFA for DHCD, February 2020.
So what changed between 2020 and 2023 that produced a number seven times larger? VHFA answered that question themselves — in a slide deck presented to the Vermont Legislature.
What Changed: Three New Components
On April 12, 2023, VHFA Executive Director Maura Collins presented to the Vermont House Energy and Environment Committee, which was considering S.100 — the bill that became the HOME Act. The presentation broke the 40,000 figure into its component parts and labeled each one. In VHFA’s own words:
Slide 9, Maura Collins / VHFA presentation to the Vermont House Energy and Environment Committee, April 12, 2023. Vermont public legislative record.
Those question marks on the right side of the slide are not editorial characterization. They are VHFA’s own language, on their own slide, in their own presentation to the committee writing the law.
Here’s what each new component actually means:
Component 1 — Vacancy normalization: 11,023 units
Not in the 2020 model. Added in 2023. Built on a 5% vacancy target that VHFA described as “a nationally accepted standard.” Vermont’s actual long-term owner vacancy average was 1.3%. Neither owner nor rental vacancy ever reached 5% historically. At 11,023 units, this component alone exceeds the entire 5,800 figure from the 2020 assessment. It is one of five components that together build the projection to 40,000.
VHFA’s own slide asked: “Is this really needed?”
Component 2 — Housing loss replacement: 2,570 units
Not formalized in the 2020 model. Built on a 0.15% annual housing destruction rate. The April 12, 2023 presentation puts the loss at approximately 370 homes per year due to poor quality — consistent with that rate applied to Vermont’s housing stock.
Component 3 — Pandemic-era demand: adds 10,231 units over pre-pandemic
The 2020 assessment used purchased projections showing household formation of 0.18% annually — near flat. The 2023 projection introduced two scenarios built on higher household growth rates: pre-pandemic at 0.8% annually producing approximately 29,000 homes needed, and pandemic-era at 1.4% annually producing 40,000. Vermont planned from the top number.
VHFA’s own slide asked: “Exceptional growth?”
Source: Maura Collins, VHFA, House Energy and Environment Committee presentation, April 12, 2023. Vermont public legislative record. Slides 7 and 9. John Bossange, “Do we really need 40,000 new homes by 2030?” VTDigger, April 8, 2023.
The vacancy normalization component accounts for more than 11,000 of the 40,000 units. The question is what benchmark it was built on, and whether that benchmark makes sense for Vermont.
The 5% Question
The vacancy normalization component accounts for 11,023 of the 40,000 units. It rests entirely on a single benchmark: 5% vacancy as “healthy.”
To be clear: this is not 5% of the 40,000 figure. It is 5% of Vermont's total housing stock — meaning roughly 16,100 units should sit vacant at any given time for the market to be considered healthy. Vermont's actual vacancy fell well short of that target. The gap between where Vermont was and where VHFA said it should be produced the 11,023 unit component.
VHFA’s own April 12, 2023 slide laid out exactly where Vermont stood relative to that target:
Slide 7, Maura Collins / VHFA presentation to the Vermont House Energy and Environment Committee, April 12, 2023. Vermont public legislative record.
The 5% figure is a nationally accepted real estate economics benchmark — the vacancy rate at which neither landlords nor tenants have outsized market power and prices stabilize. It makes sense in high-churn urban markets with high population turnover and speculative building.
Vermont’s long-term owner vacancy average was 1.3%. Not because the market was broken. Because that’s Vermont’s normal — a small rural state with stable communities, high homeownership rates, and people who don’t move often.
If you use Vermont’s own historical norm instead of the national benchmark, the gap between current vacancy and “healthy” shrinks dramatically. So does the number of homes needed to close it. So does the 40,000 figure.
This series has not located any public challenge to the 5% benchmark before the number was embedded in statute.
Source: Maura Collins, VHFA, House Energy and Environment Committee presentation, April 12, 2023. Vermont public legislative record. Slide 7.
The benchmark problem is only part of it. The demand scenario the projection was built on had a timing problem — one the public record makes visible.
The Timing Problem
The 40,000 figure’s upper scenario was built on household growth data from 2019 to 2022. That period captured Vermont’s historic migration surge. It did not capture what came next.
The IRS Statistics of Income state-to-state migration data — released March 2026 and analyzed directly by this series — shows the reversal in three steps:
The January 2023 blog post was published when the 2021–2022 data would have been available. The IRS releases state-to-state migration files on an approximately 18-month lag. The trend the pandemic-era scenario was built on had already reversed before the projection went public.
VHFA published a post on April 3, 2023 addressing the 40,000 figure. It does not acknowledge the reversal in the underlying household flow data. It does not note that net household gain had declined 75% from its peak and was months from going negative.
The 2024 Housing Needs Assessment — released in August 2024, two months after Act 181 passed — produced a lower figure: 24,000–36,000 by 2029. It does not explain what changed. This series has not located any public reconciliation of that revision with the figure already embedded in statute.
Act 181 passed in June 2024. The revised assessment came two months later.
Source: IRS Statistics of Income, State-to-State Migration Data, 2020–2023, analyzed directly by this series. VHFA blog post, April 3, 2023. VHFA/DHCD 2025–2029 Housing Needs Assessment, August 2024.
The migration trend problem isn’t the only structural issue the methodology carries. Vermont’s housing stock has a feature the vacancy calculation doesn’t fully account for.
The Seasonal Housing Problem
Vermont’s vacancy gap — the distance between current vacancy rates and the 5% target — accounts for 11,023 of the 40,000 units. But the gap calculation has a structural problem the methodology doesn’t address.
The 2020 Housing Needs Assessment — authored by Leslie Black-Plumeau — documented that 17% of Vermont’s housing stock consists of seasonal or vacation homes. Vermont has the second-highest rate in the nation. Those homes are structurally unavailable for year-round occupancy regardless of how many new units get built. The people who own them chose not to make them primary residences. Building 40,000 homes does not convert a single ski chalet in Stowe or a lakefront camp in Addison County into a year-round rental.
The vacancy normalization component targets 5% across Vermont’s entire housing stock. If 17% of that stock cannot realistically absorb year-round residents, the gap the methodology is trying to close is considerably smaller than the numbers suggest.
Then there is this. The 2025 Housing Needs Assessment states the model assumes 15% of new homes added will be acquired as second homes — based on historic usage patterns. Applied to the lower end of the target range, that means roughly 4,200 of the 27,867 homes Vermont is targeting will immediately re-enter the seasonal category that the vacancy normalization component treats as a shortage to fill.
The report that documents the seasonal constraint also projects that new construction will partially replicate it.
In plain terms: the methodology is building to solve a problem it is simultaneously recreating.
VHFA's own presentation asked the question directly: is this a housing supply problem or an occupancy problem? That's worth sitting with. If 17% of Vermont's homes are vacation properties that can't be rented year-round, and new construction keeps partially adding to that pile, then building more homes may not close the gap. Vermont's own history says a 1.3% vacancy rate is normal here — not broken. The national 5% benchmark was built for cities where people move in and out constantly. Vermont isn't that. The math points somewhere worth looking.
Source: 2020 Vermont Housing Needs Assessment, February 2020, p.4. VHFA/DHCD/VAPDA Housing Targets Appendix, January 2025, methodology section.
Behind all of these methodology questions is one person — the researcher who produced every version of this number, across every planning cycle, for the same agency.
The Analyst
Leslie Black-Plumeau is listed as a primary contributor to the 2020 Housing Needs Assessment that produced 5,800. She is the author of the January 2023 blog post that produced 40,000. She is a named contributor to the August 2024 assessment that produced 24,000–36,000. She is a named contributor to the January 2025 Housing Targets Appendix that produced 27,867–41,185.
Her VHFA biography describes 25 years of professional experience in program evaluation and public policy research, including prior work as a Congressional housing and community development program evaluator at the U.S. Government Accountability Office in Washington, D.C. Her current title at VHFA is Research and Community Relations Director.
Since 2003, she has simultaneously served as president of Black-Plumeau Consulting LLC. In her right-of-reply response to this series, Black-Plumeau confirmed that as a consultant to the Department of Children and Families, she prepared quarterly Reach Up caseload forecasts through July 2025, based on program entries, exits, and the statewide unemployment rate. The Vermont Legislative Joint Fiscal Office’s own published records document the firm’s work on those forecasts as far back as October 2021.
On February 15–16, 2023 — three weeks after the VHFA blog post and during the legislative session considering the HOME Act — Black-Plumeau submitted written testimony to the Vermont legislature. She submitted it in her personal capacity, describing herself as a 25-year Vermont resident. The testimony cited the 40,000 figure and reproduced a chart from VHFA’s own housing data. In her right-of-reply response, she confirmed: “Yes, I submitted a personal statement for the public hearing on 2/16/2023.” She did not address whether she identified her VHFA role when submitting in personal capacity.
In March 2025 — after the 40,000 figure had been embedded in statute — she joined the board of the Public Assets Institute. In her right-of-reply response, she confirmed this is accurate. PAI is a Vermont member of the State Priorities Partnership, a national network of more than 40 state policy organizations coordinated by the Center on Budget and Policy Priorities in Washington, D.C. The partnership launched in 1993 with funding from the Ford Foundation, the Annie E. Casey Foundation, and the Charles Stewart Mott Foundation. The Rockefeller Foundation granted $500,000 to CBPP for the network in 2020.
In her right-of-reply response, Black-Plumeau offered three explanations for the methodology changes between the 2020 and 2023 assessments. She described a shift from purchased third-party household projections to VHFA’s own internally developed methodology since 2019. She cited updated Census data, with the 2020 Decennial Census replacing the 2010-based estimates used in the prior assessment. And she pointed to pandemic-era changes including a small population increase, rising homelessness, and slowed home building that reduced vacancy rates. She also suggested the series consider the role of shrinking household size as a driver of housing demand. These are her explanations. The methodology choices the series documents — the 5% vacancy benchmark, the pandemic-era upper scenario, the components added between 2020 and 2023 — remain in the record as documented.
The series does not characterize any of this as improper. Vermont’s conflict of interest standard is narrow by design. What the record shows is that the researcher who produced both the floor and the ceiling of Vermont’s documented housing need simultaneously held outside consulting contracts producing quantitative forecasts for Vermont legislative committees through July 2025; submitted personal testimony in support of legislation built on her own agency’s figures without addressing her institutional role in that capacity; and subsequently joined the board of a Vermont member organization of a nationally coordinated policy network — after the number she produced became law.
Source: VHFA staff biography, Leslie Black-Plumeau, vhfa.org. Black-Plumeau Consulting LLC, Reach Up caseload forecast, October 2021, Vermont Legislature Joint Fiscal Office published records. Leslie Black-Plumeau, right-of-reply correspondence to this series, April 15, 2026. Rutland Herald, March 21, 2025. InfluenceWatch, State Priorities Partnership. CBPP, cbpp.org. Rockefeller Foundation grant, 2020.
What the Record Shows and What It Doesn’t
The record shows a housing projection that grew sevenfold between 2020 and 2023 through documented changes in methodology: three new components added, a demand scenario built on pandemic-era data that had already reversed, a vacancy target significantly above Vermont’s own historical norm, and a seasonal housing constraint the methodology does not fully account for.
The record shows the same researcher produced both the 5,800 figure and the 40,000 figure, over the same federal planning cycle, for the same agency.
The record shows the vacancy normalization component — built on a nationally accepted benchmark rather than Vermont’s historical norm — accounts for 11,023 of the 40,000 units. This series has not located any public challenge to that benchmark before the number was embedded in statute.
The record shows the 2025 Housing Needs Assessment acknowledges that new construction will partially replicate the seasonal constraint that inflates the apparent shortage.
The record shows the figure originated in a self-published agency blog post and traveled to the HOME Act, to Act 181, to DHCD regional planning targets distributed to every Vermont town. This series has not located any publicly documented independent verification at any stage of that journey.
The record shows the same agency revised the figure downward two months after Act 181 passed. This series has not located any public reconciliation of that revision with the number already in statute.
The record does not show that Vermont’s housing shortage is not real. Genuine affordability pressures, vacancy constraints, and workforce housing deficits are documented. What the record shows is that the specific number used to restructure Vermont land use was produced through a methodology that expanded significantly between 2020 and 2023, and has since been revised downward by the same agency that produced it — after the law passed.
What Comes Next
The number is one thread in a larger fabric. Part IX examines what the process record shows — the stakeholder failure, the consensus that wasn’t, and what happened when the chair of the committee that built Act 181 confirmed what the record had been showing all along.
Primary Sources
2020 Vermont Housing Needs Assessment. Vermont Housing Finance Agency for DHCD, February 2020.
Leslie Black-Plumeau, VHFA, “30,000–40,000 More Vermont Homes Needed by 2030,” January 25, 2023. vhfa.org.
Leslie Black-Plumeau, VHFA, “Why Vermont Needs 30,000–40,000 More Homes,” April 3, 2023. vhfa.org.
Maura Collins, VHFA Executive Director, House Energy and Environment Committee presentation, April 12, 2023. Vermont public legislative record. Slides 7 and 9. Committee confirmed by Maura Collins in right-of-reply correspondence to this series, April 15, 2026.
John Bossange, “Do we really need 40,000 new homes by 2030?” VTDigger, April 8, 2023.
Vermont Housing Finance Agency, 2025–2029 Housing Needs Assessment, August 2024. Produced for DHCD.
Vermont Housing Finance Agency / DHCD / VAPDA, Housing Targets Appendix, January 2025.
IRS Statistics of Income, State-to-State Migration Data, 2020–2023. Analyzed directly by this series.
DHCD press release, “New Regional Housing Targets and Housing Data Dashboard,” January 20, 2026.
Black-Plumeau Consulting LLC, Reach Up and Reach Ahead Caseload Forecast, October 2021. Vermont Legislature Joint Fiscal Office published records.
Leslie Black-Plumeau, Research and Community Relations Director, VHFA, right-of-reply correspondence to this series, April 15, 2026.
Maura Collins, Executive Director, VHFA, right-of-reply correspondence to this series, April 15, 2026.
Rutland Herald community news, March 21, 2025.
State Priorities Partnership, statepriorities.org. Center on Budget and Policy Priorities, cbpp.org. InfluenceWatch, State Priorities Partnership entry.
Rockefeller Foundation, grant to CBPP for State Priorities Partnership, 2020.
For documented findings on the stakeholder process, steering committee composition, and full series record, see Parts I through VII at alexsys.substack.com.
Data tells stories. Patterns show convergence. Curiosity validates both.
alexsys.substack.com · Part VIII
Leslie Black-Plumeau responded to this series’ right-of-reply inquiry on April 15, 2026. Her responses are incorporated in The Analyst section above. Maura Collins responded to this series’ right-of-reply inquiry on April 15, 2026. She confirmed the April 12, 2023 presentation and VHFA’s role as LBH fiscal agent. Her response is incorporated above.
Amy Sheldon has been offered multiple opportunities to respond to this series and has not responded. That is
Thank you so much for this terrific analysis, Alexsys! It is so good to have your attention on this!! Ever grateful.
I'd also love to see an analysis of our demographic projections. I suspect the housing need we do have is temporary. I'd love to see how the numbers move through the future as baby boomers age out. What scenarios are we setting ourselves up for with different levels of housing stock? Do we move from a shortage to an excess and what are the economic and societal repercussions of that?