Index Insights: April

April 2025 was one of the most volatile and active periods in recent market history as investors and traders assessed the impact of the Trump administration’s tariff announcement after the market close on April 2.

The Cboe S&P 500® Index (SPX), which had been averaging 1% daily moves in March, declined nearly 10% over the following two sessions. The VIX® Index, already elevated near 30 ahead of the tariff news, increased into the mid-50s during several intense trading days. One-month realized volatility increased to nearly 43%—the highest level since 2020.

On April 4, amid a 6% intraday selloff in the S&P 500, the options industry set a new volume record with 101 million contracts traded—nearly 15 million above the previous high. SPX options alone set a new single-day record with 6.04 million contracts traded, breaking the prior 4.85 million benchmark.

Volatility remained high heading into the 90-day tariff “pause” announced on April 9, which triggered a massive rebound in the market. SPX increased nearly 10% in a single session, its biggest gain since the early days of the COVID-19 pandemic in 2020. By month-end, markets had clawed back most of their losses, with SPX down less than 1% and the Russell 2000 off 2.4%.

With volatility and correlation spiking early in the month, indices with long optionality exposure performed best. The Cboe VIX Tail Hedge Index (VXTH) ended April up more than 3%.

Cboe’s newly launched Bitcoin ETF indices—CBTX and MBTX—also delivered strong returns, as crypto rebounded from March lows and appeared to act as a safe haven amid the equity selloff.

Equity Indices

^{Source: Cboe Global Markets}

The Russell 2000^sm Index (RUT) measures the performance of small-cap segment of the U.S. equity universe. It is a subset of the Russell 3000® Index and includes approximately 2,000 securities based on a combination of their market cap and current index membership. RUT options are valuable tools for increasing yields and managing risk. The Cboe S&P 500® Index option contract (SPX) is designed to track the underlying S&P 500 Index and help investors achieve broad market protection. SPX® options offer the potential opportunity to manage large-cap U.S. equity exposure and execute risk management, hedging, asset allocation, and income generation strategies.

Volatility Indices

^{Source: Cboe Global Markets}

The VIX® Index is based on real-time prices of options on the S&P 500® Index (SPX) and is designed to reflect investors' consensus view of future (30-day) expected stock market volatility. Cboe 1-Day Volatility Index® (VIX1D Index) estimates expected volatility by aggregating the weighted prices of P.M.-settled S&P 500 Index (SPX) puts and calls over a wide range of strike prices. The Cboe 3-Month Volatility Index^SM (VIX3M) is designed to be a constant measure of 3-month implied volatility of the S&P 500® (SPX) Index options.

Dispersion and Correlation Indices

^{Source: Cboe Global Markets}

The Cboe S&P 500 Dispersion Index (DSPX) measures the expected dispersion in the S&P 500 Index over the next 30 calendar days, as calculated from the prices of S&P 500 Index options and the prices of single stock options of selected S&P 500 Index constituents, using a modified version of the VIX® methodology. The Cboe S&P 500 Implied Correlation Indices, including COR1M and COR6M, are the first widely disseminated market estimates of the average correlation of the stocks that comprise the S&P 500. The Cboe S&P 500 Implied Correlation Indexes offers insight into the relative cost of SPX options compared to the price of options on individual stocks that comprise the S&P 500.

BuyWrite Indices – Equity

^{Source: Cboe Global Markets}

The Cboe® MSCI Emerging Markets BuyWrite Index (BXEF) is a benchmark index designed to track the performance of a hypothetical buy-write strategy on the MXEF® index. The Cboe S&P 500 BuyWrite® Index (BXM) is a benchmark index designed to track the performance of a hypothetical buy-write strategy on the S&P 500 Index®. The Cboe S&P 500 Half BuyWrite Index (BXMH) is a benchmark index designed to track the performance of a hypothetical covered call strategy. The BXMH Index is similar in design to the Cboe S&P 500 BuyWrite^SM Index (BXM). However, the difference in methodology is as follows: the strategy only writes half a unit of an ATM monthly SPX call option while the long SPX Index position remains unchanged. The Cboe Validus S&P 500® Dynamic Call BuyWrite^SM Index (CALD) tracks the value of a hypothetical rules-based investment strategy which consists of overlaying a basket of S&P 500 a.m.-settled standard expiry short call options over a long position invested in the S&P 500 with dividends reinvested (total return).

PutWrite Indices

^{Source: Cboe Global Markets}

The Cboe S&P 500 PutWrite^sm Index (PUT) tracks the value of a hypothetical portfolio of securities (PUT portfolio) that yields a buffered exposure to S&P 500 stock returns. The PUT portfolio is composed of one- and three-month Treasury bills and of a short position in at-the-money put options on the S&P 500 Index (SPX puts). The number of puts sold is selected to ensure that the value of the portfolio does not become negative when the portfolio is rebalanced. The Cboe Validus S&P 500 Dynamic PutWrite Index (PUTD) is designed to track the value of a rule-based investment strategy which consists of overlaying a basket of S&P 500 (SPX) a.m. settled standard-expiry short put options over a money market account invested at the 4-week daily Treasury Bill rate. The Cboe Russell 2000 PutWrite^sm Index (PUTR) tracks the value of a hypothetical portfolio of securities (PUTR portfolio) that yields a buffered exposure to Russell 2000 Index stock returns. The PUTR portfolio is composed of an investment of $K in one-month Treasury bills and of a short position in an at-the-money puts on the Russell 2000 Index (RUT put), where K is the strike price of the put option.

BuyWrite Indices – Fixed Income

^{Source: Cboe Global Markets}

The Cboe HYG BuyWrite Index (BXHB) is designed to track the performance of a covered call strategy with a short iShares iBoxx $ High Yield Corporate Bond ETF (HYG) call option expiring monthly. The Cboe LQD BuyWrite Index (BXLB) is designed to track the performance of a covered call strategy with a short iShares iBoxx $ Investment Grade Corporate Bond ETF (LQD) Call option expiring monthly. The Cboe TLT 2% OTM BuyWrite Index (BXTB) is designed to track the performance of a covered call strategy with a short iShares 20+ Year Treasury Bond ETF (TLT) Call option expiring monthly.

Target Outcome Series

^{Source: Cboe Global Markets}

The Cboe S&P 500 Enhanced Growth Index Series (SPEN) and Cboe S&P 500 Buffer Protect Index Series (SPRO) are part of a family of Target Outcome Indices. The Indices are designed to provide target outcome returns linked to the U.S. domestic stock market. The indices measure the performance of a portfolio of hypothetical exchange traded Flexible Exchange® Options ("FLEX® Options") that are based on the S&P 500® Index.

Protective Put Indices

^{Source: Cboe Global Markets}

The Cboe VIX Tail Hedge Index (VXTH) tracks the performance of a hypothetical portfolio that:

• Buys and holds the performance of the S&P 500 Index (the total return index, with dividends reinvested), and
• Buys one-month 30-delta call options on the Cboe Volatility Index (VIX). New VIX calls are purchased monthly, a procedure known as the "roll." The weight of the VIX calls in the portfolio varies at each roll and depends on the forward value of VIX, an indicator for the perceived probability of a "swan event."
• The weights are determined according to this schedule, and the weights applied at a particular roll date can be seen by opening the VXTH Monthly Roll Spreadsheet.

Bitcoin ETF Indices

^{Source: Cboe Global Markets}

Cboe Bitcoin U.S. ETF Index (CBTX) options and Cboe Mini Bitcoin U.S. ETF Index (MBTX) options offer tools to hedge, capitalize on price movements, or express directional views on the world’s largest cryptocurrency without holding the asset.

• Comprised of ten listed spot Bitcoin ETFs
• Options on standard (CBTX) and mini index (MBTX), as well as FLEX options contracts
• Provides exposure to spot Bitcoin price movements through options, expanding investor access to crypto derivatives

^{The information herein is provided solely for informational purposes. Past performance of an index or financial product is not indicative of future results. Indices are not financial products that can be invested in directly, but they can be used as the basis for financial products (for example, without limitation, options, futures, mutual funds or exchange-traded funds) or to help manage portfolios. Nothing herein should be construed as investment advice}

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