# NYC population change in Mamdani's first 18 months? 2025-2027 Updated: April 29, 2026 Category: Politics Tags: Local HTML: /markets/politics/local/nyc-population-change-in-mamdani-s-first-18-months/ ## Short Answer **Key takeaway.** Both the **model** and the **market** expect a decrease of 0-**0.99%** in NYC's population during Mamdani's first 18 months, with no compelling evidence of mispricing. ## Key Claims (January 2026) **- - Mamdani's proposed tax increases target high-income earners.** - Tax hikes are projected to cause 1-**2%** net out-migration from NYC. - "Good Cause" eviction laws are expected to deter new housing development. - NYPD budget cuts could negatively impact public safety perception. - These policies collectively create disincentives for NYC population growth. ### Why This Matters (GEO) - AI agents extract claims, not arguments. - Improves citation probability in summaries and answer cards. - Enables fact stitching across multiple sources. ## Executive Verdict **Key takeaway.** **Model** sees **11.5%** **probability** vs 6c **market** price, implying a 16.7x payout multiple due to policies deterring population growth. ### Who Wins and Why | Outcome | Market | Model | Why | | --- | --- | --- | --- | | Decrease 0-0.99% | 48.0% | 38.0% | Market higher by 10.0pp | | Increase 0.01-0.99% | 40.0% | 20.0% | Market higher by 20.0pp | | Decrease 1-1.99% | 8.0% | 10.3% | Model higher by 2.3pp | ## Model vs Market | Outcome | Market Probability | Octagon Model Probability | | --- | --- | --- | | Decrease 0-0.99% | 48.0% | 38.0% | | Increase 0.01-0.99% | 40.0% | 20.0% | | Decrease 1-1.99% | 8.0% | 10.3% | | Decrease 3% or more | 6.0% | 11.5% | | Increase 1-1.99% | 9.0% | 5.1% | | Increase 3% or more | 5.0% | 2.7% | | Decrease 2-2.99% | 5.0% | 9.7% | | Increase 2-2.99% | 5.0% | 2.7% | - Expiration: June 1, 2028 ## Market Behavior & Price Dynamics This market has experienced a distinct downward price movement followed by a period of stabilization. Opening at a 10.0% probability, the price fell significantly over a short period, as seen in the drop to 6.0% by late April 2026. Since this decline, the price has remained flat, establishing an overall sideways trend at the bottom of its trading range. The initial 4-percentage-point drop from 10.0% to 6.0% represents the most significant price action in the market's history. No specific context or news has been provided to explain this sharp decrease in perceived probability. Trading volume for this market is exceptionally low, with a total of only 88 contracts traded. This low liquidity suggests that price movements may be driven by a small number of participants and may not reflect a broad market consensus. The lack of significant volume during the price drop and subsequent stabilization indicates low conviction or limited interest from traders. The price appears to have found a support level at the 6.0% mark, which is both the current price and the low point of the trading range. The opening price of 10.0% acted as an early resistance level that was never retested. Overall, the chart indicates a pessimistic market sentiment regarding the likelihood of the specified population change. The price action reflects an early, decisive shift away from the initial 10.0% probability, with the market now assessing the event as having a very low chance of occurring. The subsequent flatline at 6.0%, combined with minimal trading activity, suggests this pessimistic outlook has become entrenched, with little new information or trading interest to challenge the current price. ## Significant Price Movements ### Outcome: Decrease 0-0.99% #### πŸ“‰ April 27, 2026: 9.0pp drop Price decreased from 53.0% to 44.0% **What happened:** No supporting research available for this anomaly. #### πŸ“‰ April 22, 2026: 9.0pp drop Price decreased from 60.0% to 51.0% **What happened:** No supporting research available for this anomaly. #### πŸ“‰ April 18, 2026: 8.0pp drop Price decreased from 66.0% to 58.0% **What happened:** No supporting research available for this anomaly. #### πŸ“‰ April 17, 2026: 15.0pp drop Price decreased from 81.0% to 66.0% **What happened:** No supporting research available for this anomaly. ### Outcome: Increase 0.01-0.99% #### πŸ“ˆ April 20, 2026: 11.0pp spike Price increased from 24.0% to 35.0% **What happened:** No supporting research available for this anomaly. ## Contract Snapshot The market resolves to "Yes" if New York City's population experiences an "increase" of between -0.99% to 0% from July 1, 2025, to July 1, 2027. This population change is calculated from United States Census Bureau data as ((July 2027 Population - July 2025 Population) / July 2025 Population) Γ— 100, rounded to one decimal place. The market resolves to "No" if this "Yes" condition is not met, or if the required data is unavailable by the final expiration date, which is May 31, 2028, at 11:59pm EDT (or earlier if the outcome is confirmed). Preliminary data is valid if final data is not available, and if the geography splits, the combined population of successor entities will be used. ## Market Discussion Traders are debating whether NYC's population will increase or decrease during Mamdani's initial 18 months, with current odds slightly favoring a 0-0.99% decrease (48%). Arguments for a decrease include concerns about gentrification, lack of employment, and reports of a large exodus from the city. Conversely, those betting on an increase cite "freebies" and "importing 3rd world migrants," though this is countered by skepticism regarding economic sustainability. The discussion highlights a strong political divide influencing population projections, with no clear consensus emerging. ## Market Data | Contract | Yes Bid | Yes Ask | Last Price | Volume | Open Interest | | --- | --- | --- | --- | --- | --- | | Increase 0.01-0.99% | 39% | 46% | 40% | $10,159.35 | $6,176.78 | | Decrease 0-0.99% | 46% | 48% | 48% | $16,100.36 | $8,036.75 | | Increase 1-1.99% | 3% | 7% | 9% | $5,575.75 | $3,113.75 | | Decrease 1-1.99% | 6% | 8% | 8% | $7,328.74 | $4,536.74 | | Increase 2-2.99% | 0% | 5% | 5% | $2,652.76 | $2,268 | | Decrease 2-2.99% | 0% | 5% | 5% | $2,955.3 | $2,542.3 | | Increase 3% or more | 0% | 5% | 5% | $4,286.17 | $2,432.17 | | Decrease 3% or more | 0% | 6% | 6% | $7,116.24 | $4,593.24 | ## What Tax Reforms Does Mamdani Propose for New York City? Top Individual Income Tax | 10.9% for income over $1 million [[^]](https://beta.gothamist.com/news/mamdani-wants-to-change-the-tax-code-heres-what-that-could-look-like) | Corporate Profits Tax | 4% on profits over $1 million [[^]](https://beta.gothamist.com/news/mamdani-wants-to-change-the-tax-code-heres-what-that-could-look-like) | Estate Tax Threshold | Reduced to $750,000 [[^]](https://beta.gothamist.com/news/mamdani-wants-to-change-the-tax-code-heres-what-that-could-look-like) | **Mamdani's platform targets high-income individuals and corporations with new taxes** Mamdani's platform targets high-income individuals and corporations with new taxes. For individuals earning over **$500,000,** the plan proposes raising the city's personal income tax (PIT) rate to **4.5%** on adjusted gross income (AGI) above this threshold [[^]](https://www.empirecenter.org/publications/parsing-the-impact-of-mamdanis-tax-hike-plans/). Additionally, a new top income tax bracket of **10.9%** would be introduced for those earning over **$1** million annually [[^]](https://beta.gothamist.com/news/mamdani-wants-to-change-the-tax-code-heres-what-that-could-look-like). For corporations, Mamdani advocates for a new **4%** corporate profits tax, which would apply to businesses with more than **$1** million in taxable income [[^]](https://beta.gothamist.com/news/mamdani-wants-to-change-the-tax-code-heres-what-that-could-look-like). Mamdani also proposes significant changes to the estate tax threshold. He plans to significantly reduce the estate tax threshold by **90%**, bringing it down from the current **$6.1** million to **$750,000** [[^]](https://beta.gothamist.com/news/mamdani-wants-to-change-the-tax-code-heres-what-that-could-look-like). This change would also introduce a top estate tax rate of **20%** [[^]](https://beta.gothamist.com/news/mamdani-wants-to-change-the-tax-code-heres-what-that-could-look-like). Based on historical tax elasticity studies by the NYC Independent Budget Office (IBO), it is projected that for every **10%** increase in the income tax rate, approximately **1%** to **2%** of high-income earners would migrate out of the city [[^]](https://beta.gothamist.com/news/mamdani-wants-to-change-the-tax-code-heres-what-that-could-look-like). ## What are the potential impacts of 'Good Cause' eviction laws? Proposed Eviction Law Scope | Universal "Good Cause" eviction law city-wide [[^]](https://www.zohranfornyc.com/policies/housing-by-and-for-new-york) | New Construction Permits Decline | 12.3% fall (post-HSTPA) [[^]](https://furmancenter.org/files/Rent_Reform_7_1_A_remediated.pdf) | Rent-Stabilized Property Sales Price Decline | 7.7% for 100% rent-stabilized units (post-HSTPA) [[^]](https://furmancenter.org/files/Rent_Reform_7_1_A_remediated.pdf) | **Zohran Mamdani's campaign proposes universal "Good Cause" eviction city-wide** Zohran Mamdani's campaign proposes universal "Good Cause" eviction city-wide. The campaign plans to implement a universal "Good Cause" eviction law across New York City, which aims to protect all tenants from arbitrary evictions [[^]](https://www.zohranfornyc.com/policies/housing-by-and-for-new-york). This initiative seeks to ensure housing stability for renters by removing landlords' ability to evict without specific, legally defined reasons, such as non-payment of rent or breach of lease [[^]](https://www.zohranfornyc.com/policies/housing-by-and-for-new-york). Analysts forecast negative impacts on housing construction and property values. Analyses from the NYU Furman Center express concern that "Good Cause" eviction policies could deter new residential construction and investment in existing properties, potentially worsening the city’s housing supply shortage [[^]](https://furmancenter.org/files/publications/Balancing_act.pdf). Specifically, prior research on the Housing Stability and Tenant Protection Act (HSTPA) noted a **12.3%** fall in new residential construction permits within six months of its enactment [[^]](https://furmancenter.org/files/Rent_Reform_7_1_A_remediated.pdf). The same analysis observed a **7.7%** decrease in sales prices for buildings composed entirely of rent-stabilized units, and a **3.9%** drop for those with 75-**99%** rent-stabilized units following HSTPA's implementation [[^]](https://furmancenter.org/files/Rent_Reform_7_1_A_remediated.pdf). The Rent Stabilization Association (RSA) also forecasts that such a law would "stifle new housing construction" and "devalue rental properties" [[^]](https://therealdeal.com/new-york/2024/02/29/the-unintended-consequences-of-good-cause-eviction/). ## What Are Mamdani's Policies for NYC Asylum Seeker Influx? Primary Policy Focus | Phasing out emergency shelters, transitioning to stable solutions [[^]](https://citylimits.org/mamdani-to-phase-out-emergency-shelters-for-migrants-that-dont-meet-city-standards/) | Target Year for Emergency Shelter End | 2026 [[^]](https://www.thecity.nyc/2026/01/06/mamdani-executive-order-migrant-shelters/) | Historical Monthly Asylum Seeker Increase | Approximately 2,000 per month (May 2023 - May 2024) [9, p.3] [[^]](https://citylimits.org/mamdani-to-phase-out-emergency-shelters-for-migrants-that-dont-meet-city-standards/) | **Mamdani's policies aim to systematically eliminate temporary emergency migrant shelters** Mamdani's policies aim to systematically eliminate temporary emergency migrant shelters. The proposals for New York City's 'right to shelter' mandate for asylum seekers focus on phasing out and eventually discontinuing these facilities. Mayor Mamdani has initiated a comprehensive review of all city shelters for migrants, with plans to close emergency facilities that do not meet city standards [[^]](https://citylimits.org/mamdani-to-phase-out-emergency-shelters-for-migrants-that-dont-meet-city-standards/). A core component of these policies involves transitioning asylum seekers from temporary accommodations to more permanent housing options or facilitating their departure from New York City [[^]](https://mamdanipost.com/the-right-to-a-bed-mamdani-confronts-new-yorks-deepest-homelessness-crisis/). An executive order was reportedly issued in 2026 to cease the use of such emergency migrant shelters, with the ultimate goal to close the last emergency facility by the end of that year [[^]](https://www.thecity.nyc/2026/01/06/mamdani-executive-order-migrant-shelters/). No specific projected monthly influx data exists for Mamdani's new policies. While Mamdani's initiatives are designed to reduce reliance on temporary shelters, the available research does not provide a specific projected monthly net influx under these proposed changes. However, data from the NYC Council indicates an average monthly increase of approximately 2,000 asylum seekers in the City's care between May 2023 and May 2024 [9, p.3]. ## What are Zohran Mamdani's Proposed NYPD Budget Cuts and Staffing Changes? Proposed NYPD Budget Cut | $3 billion [[^]](https://www.thecity.nyc/2026/04/10/nypd-zohran-mamdani-100-days-accountabilty-crime-policing/) | Percentage of NYPD Budget Reallocated | Approximately 47% [[^]](https://www.thecity.nyc/2026/04/10/nypd-zohran-mamdani-100-days-accountabilty-crime-policing/) | Proposed New Officer Hires Canceled | 5,000 [[^]](https://www.foxnews.com/politics/mamdani-proposes-cutting-nypd-budget-canceling-5k-new-officer-hires) | **Zohran Mamdani proposes a significant NYPD budget cut and hiring freeze** Zohran Mamdani proposes a significant NYPD budget cut and hiring freeze. He has put forward a plan to reallocate approximately **47%** from the New York City Police Department's estimated **$6.4** billion budget for the upcoming fiscal year. This proposal amounts to a **$3** billion reduction for the department [[^]](https://www.thecity.nyc/2026/04/10/nypd-zohran-mamdani-100-days-accountabilty-crime-policing/) and includes canceling the hiring of 5,000 new police officers [[^]](https://www.foxnews.com/politics/mamdani-proposes-cutting-nypd-budget-canceling-5k-new-officer-hires). The proposed headcount would fall within the 2020-2022 crime spike levels. If the cancellation of 5,000 new hires proceeds, the NYPD's uniformed headcount would remain near its current level of approximately 33,594 officers, as recorded in December 2023 [[^]](https://www1.nyc.gov/site/nypd/stats/reports-analysis/staffing-report.page). This staffing level is within the range observed during the 2020-2022 period, which saw a crime spike, with headcounts fluctuating from 35,015 in Fiscal Year 2020 to 31,762 by December 2022 [[^]](https://www.osc.ny.gov/files/reports/osdc/pdf/nypd-issue-brief.pdf). Therefore, the proposed force size would be higher than the December 2022 low but lower than the Fiscal Year 2020 peak [[^]](https://www.osc.ny.gov/files/reports/osdc/pdf/nypd-issue-brief.pdf). ## Which High-Frequency Indicators Signal Large NYC Population Changes? NYC Population (July 1, 2024) | 8,260,076 [[^]](https://s-media.nyc.gov/agencies/dcp/assets/files/pdf/data-tools/population/population-estimates/new-york-city-population-estimates-and-trends-march-2026.pdf) | Annual 1.5% Population Change | Over 123,901 people [[^]](https://s-media.nyc.gov/agencies/dcp/assets/files/pdf/data-tools/population/population-estimates/new-york-city-population-estimates-and-trends-march-2026.pdf) | Key Population Indicators | USPS change-of-address, public school enrollment [[^]](https://s-media.nyc.gov/agencies/dcp/assets/files/pdf/data-tools/population/population-estimates/new-york-city-population-estimates-and-trends-march-2026.pdf) | **New York City's population changes are tracked by specific high-frequency indicators** New York City's population changes are tracked by specific high-frequency indicators. New York City's population was estimated at 8,260,076 as of July 1, 2024 [[^]](https://s-media.nyc.gov/agencies/dcp/assets/files/pdf/data-tools/population/population-estimates/new-york-city-population-estimates-and-trends-march-2026.pdf). A net annual population change exceeding **1.5%** would translate to an increase or decrease of over 123,901 people annually. High-frequency indicators with strong historical correlation to NYC's annual population estimates include net USPS change-of-address requests and public school enrollment data, which provide timely insights into migration patterns and family movements [[^]](https://s-media.nyc.gov/agencies/dcp/assets/files/pdf/data-tools/population/population-estimates/new-york-city-population-estimates-and-trends-march-2026.pdf). Significant population shifts require dramatic reversals in indicator trends. For a net annual population increase exceeding **1.5%** in NYC from Q1 2026 to Q2 2027, these indicators would need to show a dramatic reversal of recent trends. USPS change-of-address data would require a sustained and substantial net inflow of residents, moving from current net out-migration to a significant net in-migration [[^]](https://s-media.nyc.gov/agencies/dcp/assets/files/pdf/data-tools/population/population-estimates/new-york-city-population-estimates-and-trends-march-2026.pdf). Concurrently, public school enrollment data would need to demonstrate a substantial and consistent increase in student numbers, indicating a strong influx of families into the city [[^]](https://s-media.nyc.gov/agencies/dcp/assets/files/pdf/data-tools/population/population-estimates/current-population-estimates-march-2025-release.pdf). Conversely, for a net annual population decrease exceeding **1.5%**, USPS change-of-address data would need to reflect an accelerated and pronounced net out-migration [[^]](https://s-media.nyc.gov/agencies/dcp/assets/files/pdf/data-tools/population/population-estimates/current-population-estimates-march-2025-release.pdf). Public school enrollment figures would likewise need to show an intensified and sustained decline, signaling a significant outflow of families with children [[^]](https://s-media.nyc.gov/agencies/dcp/assets/files/pdf/data-tools/population/population-estimates/current-population-estimates-march-2025-release.pdf). The New York City Department of City Planning currently projects a period of moderate growth for the city starting around mid-2024, anticipating a return to pre-pandemic peak population around 2029 [[^]](https://s-media.nyc.gov/agencies/dcp/assets/files/pdf/data-tools/population/population-estimates/new-york-city-population-estimates-and-trends-march-2026.pdf). ## What Could Change the Odds **Key takeaway.** Catalyst analysis unavailable. ## Key Dates & Catalysts - **Expiration:** June 01, 2029 - **Closes:** June 01, 2028 ## Decision-Flipping Events - Catalyst analysis unavailable. ## Related Research Reports - [EU has a new member before 2030?](/markets/politics/international/eu-has-a-new-member-before-2030/) - [Will Trump's birthright citizenship order come into effect?](/markets/politics/scotus-courts/will-trump-s-birthright-citizenship-order-come-into-effect/) - [Will Trump create a $250 bill featuring himself?](/markets/politics/congress/will-trump-create-a-250-bill-featuring-himself/) - [Which countries will normalize relations with Israel before 2027?](/markets/politics/international/which-countries-will-normalize-relations-with-israel-before-2027/) ## Historical Resolutions No historical resolution data available for this series. ## Disclaimer This content is for informational and educational purposes only and does not constitute financial, investment, legal, or trading advice. Prediction markets involve risk of loss. Past performance does not guarantee future results. We are not affiliated with Kalshi or any prediction market platform. Market data may be delayed or incomplete. ### Data Sources & Model Transparency **Data Sources:** Octagon Deep Research aggregates information from multiple sources including news, filings, and market data. **Freshness:** Analysis is generated periodically and may not reflect the latest developments. Verify critical information from primary sources. ## Attribution Policy When quoting, summarizing, or reproducing Octagon AI content, attribute it to Octagon AI and link to the Octagon source URL: https://octagonai.co/markets/politics/local/nyc-population-change-in-mamdani-s-first-18-months If a specific page was used, cite that page rather than only the site homepage.