S&P 100
The S&P 100 is a stock market index comprising 100 leading large-capitalization U.S. companies selected from the S&P 500, designed to measure the performance of major blue-chip stocks across a broad range of industries.[1] Launched on June 15, 1983, by S&P Dow Jones Indices, a division of S&P Global, it serves as a key benchmark for investors seeking exposure to the largest and most liquid U.S. equities.[1] The index is constructed using a float-adjusted market-capitalization weighting methodology, where each constituent's weight is determined by its investable market capitalization, adjusted for the proportion of shares available to the public.[2] Selection of components is overseen by an Index Committee that prioritizes the 100 largest companies from the S&P 500 by float-adjusted market capitalization, with a focus on those having exchange-listed options and maintaining sector representation for diversification.[2] To mitigate concentration risk, the methodology includes caps: no single company can exceed 22.5% of the index weight (with a buffer below 25%), and the combined weight of all companies above 4.5% is limited to 45% (with a buffer below 50%).[2] Maintenance of the S&P 100 involves quarterly rebalancing after the close on the third Friday of March, June, September, and December, using data from the prior Wednesday, aligned with S&P 500 updates.[2] Corporate actions such as mergers, spin-offs, or delistings trigger immediate deletions, with additions and other changes made by the Index Committee as needed, including during quarterly rebalances, in addition to the annual reconstitution, which occurs after the third Friday in June based on the last business day of May.[2] As of March 2025, additions to the index included DoorDash, TKO Group Holdings, Williams-Sonoma, and Expand Energy.[3] The index is widely used by asset managers, options traders on the Cboe Global Markets exchange, and as a reference for exchange-traded funds like the iShares S&P 100 ETF, providing a focused view of U.S. mega-cap performance distinct from the broader S&P 500.[4]Introduction and Methodology
Definition and Purpose
The S&P 100 is a capitalization-weighted stock market index that tracks the performance of 100 leading large-cap U.S. companies, selected as a subset of the broader S&P 500, with a focus on those exhibiting high liquidity and having exchange-listed options available.[1][2] These components primarily consist of blue-chip firms from diverse sectors, representing approximately the largest and most stable entities within the U.S. equity market by float-adjusted market capitalization.[4] Launched on June 15, 1983, by S&P Dow Jones Indices, a division of S&P Global, the index was developed to address the emerging needs of the options market by providing a concentrated benchmark of top-tier, highly tradable stocks.[1][5] The primary purposes of the S&P 100 are to serve as a performance benchmark for large-cap equity investments and to underpin derivatives trading, particularly options and futures contracts traded on exchanges like the Chicago Board Options Exchange (CBOE).[2][4] Its emphasis on liquidity and blue-chip representation makes it ideal for institutional investors and traders seeking exposure to the core of the U.S. market without the broader diversification of larger indices, enabling efficient hedging and speculation strategies.[4] For instance, OEX options, which are cash-settled and based on the index, were among the first index options introduced, facilitating rapid growth in derivatives volume since their inception.[4][5] Compared to the S&P 500, which encompasses 500 companies for a more comprehensive view of the large-cap segment covering about 80% of U.S. market capitalization, the S&P 100 offers a narrower, liquidity-focused lens on the market's most prominent players, resulting in lower volatility but potentially higher concentration risk.[6][7] In contrast, the Dow Jones Industrial Average (DJIA) includes only 30 blue-chip stocks and employs a price-weighted methodology, prioritizing higher-priced shares over market cap, which makes it less representative of overall market breadth than the market-cap-weighted S&P 100.[7][8]Selection Criteria
The S&P 100 index consists of 100 leading U.S. large-cap companies selected from the constituents of the S&P 500 by the S&P U.S. Index Committee.[2] Selection emphasizes the largest companies by float-adjusted market capitalization that also have exchange-listed options available, ensuring the index serves as a benchmark for highly liquid blue-chip stocks.[2] All potential constituents must first satisfy the broader eligibility criteria established for the S&P 500.[2] Eligibility for inclusion requires companies to be U.S.-domiciled, meaning they are incorporated in the United States or have their primary operations and listing there.[2] A minimum total company-level market capitalization of at least US$22.7 billion is mandated as of July 1, 2025, positioning the S&P 100 as a subset of the top-tier S&P 500 members.[2] Additionally, companies must demonstrate financial viability through positive as-reported earnings (GAAP) in the most recent fiscal quarter and over the sum of the prior four consecutive quarters, evaluated at the company level including subsidiaries.[2] Liquidity is a core threshold, with eligible securities required to trade a minimum of 250,000 shares in each of the six months prior to evaluation.[2] Furthermore, the public float must represent at least 10% of total shares outstanding, and the float-adjusted liquidity ratio (FALR)—calculated as the annual dollar value traded divided by float-adjusted market capitalization—must be at least 0.75 for additions to the index.[2] These measures ensure that selected companies exhibit sufficient market depth and investability.[2] The Index Committee aims to achieve broad sector representation across the Global Industry Classification Standard (GICS) sectors without imposing strict quotas, promoting diversification while reflecting the overall composition of the U.S. large-cap market.[2] This qualitative judgment allows flexibility to include sector leaders beyond pure size rankings, maintaining balance in areas such as technology, financials, and healthcare.[2] Rebalancing occurs quarterly, with the committee reviewing the index after the close on the third Friday of March, June, September, and December; changes are effective at the open on the following Monday.[2] The reference date for these reviews is the Wednesday prior to the second Friday of the rebalance month, during which a freeze on shares and investable weight factor (IWF) updates is applied to stabilize calculations.[2] Ad-hoc adjustments are implemented for events such as mergers, acquisitions, or delistings, with additions or deletions announced as soon as practicable to preserve the index's integrity.[2] Certain security types are explicitly excluded to focus on standard equity representations of operating companies.[2] American Depositary Receipts (ADRs), master limited partnerships (MLPs), limited partnerships, and closed-end funds are ineligible.[2] Constituents must be listed exclusively on major U.S. exchanges, including the New York Stock Exchange (NYSE), Nasdaq, NYSE Arca, or NYSE American, excluding over-the-counter (OTC) markets.[2]Index Calculation
The S&P 100 index employs a float-adjusted market-capitalization weighting methodology to compute its value, reflecting the total investable market capitalization of its components relative to a divisor. The index level is calculated using the formula: \text{Index Level} = \frac{\sum_{i=1}^{n} (P_i \times Q_i)}{\text{Divisor}} where P_i is the current price of component stock i, Q_i is the number of float-adjusted shares outstanding for that stock, and n is the number of components.[9] This approach ensures that larger companies, based on their investable market value, have a greater influence on the index's movement.[2] The float adjustment is applied through the Investable Weight Factor (IWF), which modifies the total shares outstanding to include only those freely available to the public, excluding shares held by governments, strategic investors, or insiders that are not typically tradable. Thus, Q_i = total shares outstanding \times IWF, providing a more accurate representation of the shares available for investment and reducing distortions from non-investable holdings.[9] The IWF is reviewed and updated during quarterly rebalancings or as corporate actions occur.[2] To preserve the index's continuity and prevent artificial changes in its level, the divisor is adjusted in response to corporate events such as stock splits, spin-offs, mergers, or component additions and deletions. For instance, during a stock split, the share count increases proportionally, and the divisor is recalculated as \text{New Divisor} = \text{Old Divisor} \times \frac{\text{Pre-Event Market Value}}{\text{Post-Event Market Value}} to maintain the same index value immediately before and after the event.[9] Adjustments for component substitutions are announced at least three business days in advance, while other changes are implemented immediately or at the close of trading on the effective date.[2] The index is computed in real time on an intraday basis using live stock prices during market hours.[9] The S&P 100 was assigned a base value of 686.45 as of the base date December 29, 2000, with the divisor initially set to scale the aggregate float-adjusted market capitalization to this level; historical values prior to the launch date of June 15, 1983, are back-tested for analytical purposes.[2] A total return variant, the S&P 100 Total Return (S&P 100-TR), incorporates the reinvestment of dividends to capture the full economic return of the components. It is computed by adjusting the price return index level daily: \text{TR Level}_t = \text{TR Level}_{t-1} \times (1 + \text{Price Return}_t + \text{Dividend Return}_t), where the dividend return reflects gross dividends paid by components divided by the prior index level, assuming immediate reinvestment.[9] A net total return version withholds taxes on dividends for certain international applications.[2]Historical Development
Inception and Evolution
The roots of the S&P 100 index trace back to earlier efforts by Standard & Poor's to develop market benchmarks, including the S&P 90, a daily composite index of 90 stocks launched in 1926 that encompassed 50 industrial companies and served as a foundational measure of U.S. equity performance. This precursor, along with the S&P 233 weekly index from 1923, laid the groundwork for broader stock market tracking by Standard & Poor's, adapting to the needs of investors and analysts in the early 20th century. These early indices evolved to meet growing demands for reliable, representative data amid the expansion of financial markets.[10][11] The S&P 100 was formally launched by Standard & Poor's on June 15, 1983, as a subset of the S&P 500 designed specifically to support options trading on the Chicago Board Options Exchange (CBOE), which had expressed demand for a liquid, large-cap benchmark amenable to derivatives. Options based on the index, initially known as the CBOE-100 before its rebranding to the S&P 100 or OEX, began trading on the CBOE on March 11, 1983, marking the first listed index options in the U.S. and enabling institutional investors to hedge and speculate on major blue-chip stocks. The index's creation addressed the limitations of broader indices for options markets by focusing on highly liquid components.[1][12][13] At inception, the S&P 100 comprised 100 stocks drawn from the S&P 500, selected based on criteria emphasizing market capitalization, trading volume, and the presence of exchange-listed options to ensure sufficient liquidity for efficient derivatives trading. This composition targeted the largest and most established U.S. companies, capturing approximately 80% of the S&P 500's market capitalization while prioritizing those with robust options markets to minimize trading frictions. The focus on liquidity facilitated rapid adoption among traders seeking capital-efficient exposure to mega-cap equities.[2][14] In its early years during the 1980s, the index benefited from expanded data dissemination, including the introduction of real-time quotes through electronic feeds, which supported the burgeoning volume of options activity on the CBOE. By the 1990s, the S&P 100 achieved greater integration with the S&P 500 through shared computational methodologies and unified data distribution channels, enhancing consistency in performance tracking and investor access. Ownership of Standard & Poor's, the index's originator, shifted in 1966 when it was acquired by McGraw-Hill, providing expanded resources for index maintenance; in 2016, McGraw Hill Financial rebranded to S&P Global Inc., under which the S&P 100 is now overseen by S&P Dow Jones Indices. These developments solidified the index's role as a cornerstone for large-cap equity derivatives.[15][16]Key Milestones
In the early 2000s, the S&P 100 underwent methodological updates to enhance its representativeness amid market volatility following the dot-com bust. Following the dot-com bust, additions like Apple Inc. in May 2007 helped bolster technology exposure. In March 2005, S&P Dow Jones Indices transitioned to a float-adjusted market capitalization weighting scheme for the index, excluding shares held by governments, insiders, and strategic stakeholders to better reflect investable opportunities.[2] This change aimed to improve accuracy in capturing large-cap performance while maintaining sector balance in constituent selection.[2] The 2008 financial crisis marked a pivotal period of delistings for the S&P 100, reflecting the turmoil in the financial sector. Lehman Brothers, a longstanding component, was removed from the index on September 16, 2008, following its bankruptcy filing, which exacerbated market declines and led to broader adjustments in blue-chip representation.[17] This event highlighted the index's vulnerability to systemic risks, prompting subsequent additions of resilient firms. Product innovations expanded access to the S&P 100 in the 2000s and 2010s. The iShares S&P 100 ETF (OEF), the first exchange-traded fund tracking the index, launched on October 23, 2000, providing investors with a low-cost vehicle for large-cap exposure.[18] During the 2010s, integration with global benchmarks facilitated cross-border ETFs, such as those blending S&P 100 constituents with international indices, enabling diversified portfolios amid rising demand for worldwide equity products; by 2011, over 95 new S&P-linked ETFs had been introduced globally in 2010, many incorporating U.S. large-cap elements like the S&P 100.[19] Rule evolutions in the late 2010s addressed evolving market structures. In July 2017, S&P Dow Jones Indices revised eligibility criteria for U.S. indices, including the S&P 100, to require positive as-reported earnings in the most recent fiscal quarter and the sum of the prior four quarters, aiming to ensure financial stability among constituents.[20] The index maintains quarterly rebalancing in March, June, September, and December to adjust weights and compositions dynamically.[1] Recent developments underscore the S&P 100's adaptation to innovation-driven growth. Tesla Inc. joined the index on December 21, 2020, replacing Occidental Petroleum and marking the largest addition by market cap at the time, reflecting the rise of electric vehicles in large-cap portfolios.[21] Following the 2021 SPAC surge, S&P Dow Jones updated inclusion rules in February 2022, treating de-SPAC mergers as equivalent to initial public offerings and mandating at least 12 months of post-merger trading history for eligibility, to mitigate risks from unproven entities.[22] In September 2024, Palantir Technologies was added to the S&P 100, highlighting the inclusion of advanced technology firms. A reshuffle effective March 24, 2025, introduced additional companies including DoorDash and TKO Group Holdings to reflect current market leadership in consumer and entertainment sectors as of November 2025.[23][24] While ESG factors influence separate sustainable variants like the S&P 500 ESG Index, core S&P 100 selection remains focused on market cap, liquidity, and sector balance without formal quotas as of 2023.[25]Composition and Characteristics
Current Components
The S&P 100 index, as of November 2025, consists of 100 leading large-cap U.S. companies selected from the S&P 500 for their liquidity, sector balance, and market influence. The index is market-capitalization weighted, with technology firms dominating the top holdings; Microsoft Corporation (MSFT), Apple Inc. (AAPL), and NVIDIA Corporation (NVDA) collectively account for approximately 29% of the total weight, contributing to a broader technology sector allocation of around 41%. Financial services follow as the second-largest group, led by JPMorgan Chase & Co. (JPM) and Berkshire Hathaway Inc. (BRK.B), reflecting the index's emphasis on blue-chip stability and growth potential.[26][27] Throughout 2025, the S&P 100 underwent periodic rebalancing to maintain alignment with market capitalization shifts and eligibility criteria. In March, Palantir Technologies Inc. (PLTR), Intuitive Surgical Inc. (ISRG), and ServiceNow Inc. (NOW) were added, replacing Dow Inc. (DOW), The Kraft Heinz Company (KHC), and Ford Motor Company (F), effective March 24. Later, in September, Uber Technologies Inc. (UBER) joined the index, ousting Charter Communications Inc. (CHTR), effective September 22; these adjustments incorporated high-growth technology and consumer discretionary names amid evolving market dynamics. The methodology includes caps to mitigate concentration risk, with no single company exceeding 22.5% of the index weight (buffer below 25%), and the combined weight of all companies above 4.5% limited to 45% (buffer below 50%), ensuring broad representation across the 11 GICS sectors, including information technology, financials, health care, consumer discretionary, and communication services.[28][2] The index's composition has become more concentrated in technology over time, with the technology sector's allocation increasing from about 18% in 2010 to 41% in 2025, driven by the growth of major tech firms and rebalancing toward high-market-cap leaders. This evolution underscores the index's role in capturing the performance of U.S. mega-cap leaders, where technology remains pivotal.[1][29]| Company Name | Ticker | Sector | Weight (%) | Market Cap (USD) |
|---|---|---|---|---|
| NVIDIA Corporation | NVDA | Information Technology | 10.89 | $4.62T |
| Apple Inc. | AAPL | Information Technology | 9.68 | $4.04T |
| Microsoft Corporation | MSFT | Information Technology | 8.94 | $3.79T |
| Amazon.com Inc. | AMZN | Consumer Discretionary | 5.51 | $2.61T |
| Alphabet Inc. (Class A) | GOOGL | Communication Services | 3.87 | $3.37T |
| Alphabet Inc. (Class C) | GOOG | Communication Services | 3.11 | $3.37T |
| Broadcom Inc. | AVGO | Information Technology | 3.82 | $1.65T |
| Meta Platforms Inc. (Class A) | META | Communication Services | 3.16 | $1.57T |
| Tesla Inc. | TSLA | Consumer Discretionary | 2.69 | $1.43T |
| Berkshire Hathaway Inc. (Class B) | BRK.B | Financials | 2.25 | $1.08T |
| JPMorgan Chase & Co. | JPM | Financials | 2.03 | $0.86T |
| Eli Lilly and Company | LLY | Health Care | 1.94 | $0.85T |
| Visa Inc. (Class A) | V | Financials | 1.36 | $0.62T |
| Exxon Mobil Corporation | XOM | Energy | 1.21 | $0.52T |
| Johnson & Johnson | JNJ | Health Care | 1.12 | $0.38T |
| Mastercard Incorporated (Class A) | MA | Financials | 1.10 | $0.48T |
| ... (continuing with remaining constituents, including AbbVie Inc. (ABBV, Health Care, 0.98%, $0.35T), Bank of America Corporation (BAC, Financials, 0.87%, $0.32T), Coca-Cola Company (KO, Consumer Staples, 0.80%, $0.28T), and others across all 11 GICS sectors, with weights decreasing to under 0.5% for smaller holdings; full details available via official index providers) |
Sector and Industry Breakdown
The S&P 100 index exhibits a sector distribution that reflects the dominance of large-cap U.S. companies, with Information Technology comprising the largest allocation at 41.37% as of November 13, 2025, followed by Financials at 13.2%, Health Care at 12.9%, and Consumer Discretionary at 10.1%.[30] Communication Services accounts for 9.6%, Industrials 6.7%, Consumer Staples 4.2%, Energy 2.3%, Utilities 1.5%, Real Estate 1.0%, and Materials 0.7%.[18] This allocation underscores the index's heavy tilt toward growth-oriented sectors driven by innovation and consumer spending. Within the Information Technology sector, sub-industries show notable concentration, with Semiconductors & Semiconductor Equipment representing 17.19% of the overall index weight and Software & Services at 13.57% as of November 12, 2025.[18] In the Financials sector, banks dominate with approximately 8% of the index, while insurance companies contribute around 4%, reflecting the sector's reliance on traditional banking institutions amid stable interest rate environments.[18] Historically, the sector composition has shifted markedly, with the Information Technology weight rising from about 18% in 2010 to 41.37% in 2025, fueled by the explosive growth of major tech firms often referred to as FAANG stocks.[29][30] The Energy sector experienced a temporary boost post-2022, increasing to around 8% amid inflation-driven oil price surges, before settling at 2.3% by late 2025 as commodity pressures eased.[29][18] Diversification within the S&P 100 can be assessed using the Herfindahl-Hirschman Index (HHI) for sector concentration, calculated as the sum of squared sector weights, yielding approximately 0.20 based on November 2025 allocations; this value indicates moderate concentration, primarily due to the outsized Information Technology weighting.[18] Compared to the broader S&P 500, which has a similar sector HHI but lower individual stock weights, the S&P 100 appears more top-heavy, enhancing its sensitivity to mega-cap performance.[31] This sector balance influences the index's overall stability, as the prominence of Information Technology amplifies growth potential during economic expansions but heightens volatility during tech-specific downturns, such as regulatory scrutiny or supply chain disruptions.[1] In contrast, the more balanced allocations in defensive sectors like Health Care and Financials provide a buffer against cyclical risks, contributing to the index's reputation for relative resilience among large-cap benchmarks.[1]Performance Metrics
Record Values
The S&P 100 index reached its all-time closing high of 3,487.23 on October 29, 2025, following a recovery from a market correction in early 2025, driven by resilient large-cap performance amid economic uncertainties.[32] This peak built on gains from technology and other sectors, with the index surpassing prior records after rebounding from a low of approximately 2,405.92 on April 8, 2025. The index's all-time intraday high was 3,492.80 on October 29, 2025.[32] Conversely, the all-time low closing value of 322.13 occurred on March 9, 2009, at the nadir of the global financial crisis, when banking sector failures and credit market freezes led to widespread panic selling across major U.S. equities. From this bottom, the index began a prolonged recovery, surpassing 1,000 points by 2013 as monetary stimulus and economic stabilization measures took effect. During the COVID-19 market crash, the index hit a notable intraday low near 1,100 on March 23, 2020, driven by pandemic-related lockdowns and uncertainty over corporate earnings.[1] When adjusted for inflation using CPI data, the real value of the all-time high equates to approximately 3,400 points in 2025 dollars, accounting for cumulative inflation since inception. For total return, which incorporates reinvested dividends, the index has exceeded 5,000 points at its peak, underscoring the additional value from dividend payouts among its high-quality constituents.[1] Significant contextual events include the 1987 Black Monday crash, where the index dropped 22% in a single day on October 19, 1987, due to program trading and portfolio insurance amplifying sell-offs. More recently, the 2022 bear market saw the index fall to a low of approximately 1,400 amid surging inflation and aggressive Federal Reserve rate hikes, representing a roughly 25% decline from its prior highs.[33]Annual Returns
The S&P 100 index has exhibited significant year-over-year variability in its total returns, influenced by economic cycles, sector performance, and global events. Since its formal launch in 1983 (with data extending back to 1972), the index's price return has averaged approximately 10.5% annually, while the total return, which includes reinvested dividends, has averaged around 12.2% through 2024. This total return figure incorporates an average dividend yield of 1.5-2.0%, which has consistently boosted performance by 1-2 percentage points per year, providing a buffer during periods of price stagnation or decline.[1] The standard deviation of annual total returns has hovered around 15%, underscoring the index's exposure to market volatility typical of large-cap U.S. equities. Over decades, performance has shown distinct patterns: the 2010s represented a prolonged bull market with an average annual total return of 13.6%, fueled by technology and financial sector gains; in contrast, the 2020s have been marked by heightened volatility, including a robust +28% return in 2021 amid economic reopening and stimulus measures, followed by a -19% drop in 2022 due to inflation concerns and interest rate hikes.[34][1] Comparisons highlight the S&P 100's subtle edge over the broader S&P 500, with total returns approximately 0.5% higher on an annualized basis since 1983, attributable to its focus on highly liquid blue-chip stocks that reduce trading frictions. Against inflation, the index's real total return has averaged about 7%, preserving purchasing power over the long term despite periodic erosions during high-inflation years.[35] The following table summarizes select annual total returns for the S&P 100 from 1984 to 2025, highlighting key periods of growth, contraction, and recovery (data for pre-2000 reflects price returns adjusted approximately for dividends based on historical yields; post-2000 uses iShares S&P 100 ETF as a close proxy for total returns).[35][34]| Year | Total Return (%) | Key Context |
|---|---|---|
| 1984 | 6.3 | Modest recovery post-recession |
| 1985 | 26.0 | Strong bull market initiation |
| 1995 | 31.7 | Tech-driven surge |
| 2008 | -37.0 | Global financial crisis |
| 2010 | 13.0 | Post-crisis rebound |
| 2021 | 28.0 | Pandemic recovery and tech boom |
| 2022 | -19.0 | Rate hikes and growth slowdown |
| 2023 | 32.7 | AI optimism and economic resilience |
| 2024 | 30.7 | Large-cap strength and market rally |
| 2025 | 20.3 (YTD as of Nov 2025) | Recovery from early-year correction |