Markets
Fixed AI Infrastructure Basket vs. SPY Adjusted Close
A daily, fixed-base comparison of five AI infrastructure leaders—NVIDIA, Broadcom, AMD, Microsoft, and TSMC ADR—with SPY adjusted close. Every line starts at 100 on January 3, 2023; the equal-initial-dollar basket is held without rebalancing.
Fixed AI Infrastructure Basket vs. SPY Adjusted Close
- Fixed AI infrastructure basket
- SPY adjusted-close proxy
At 2026-10-21, the fixed AI infrastructure basket stood at 781.3 index (2023-01-03 = 100) versus the SPY adjusted-close proxy, with both based to 100 on January 3, 2023.
Methodology
Membership is fixed on AI-industry merits at NVIDIA (NVDA), Broadcom (AVGO), AMD (AMD), Microsoft (MSFT), and Taiwan Semiconductor Manufacturing Company ADR (TSM). Together they cover accelerators, custom silicon, networking, cloud and enterprise AI, leading-edge fabrication, and advanced packaging. Public neoclouds do not share a January 3, 2023 trading base, so they cannot enter this fixed-base series. Consumer-internet companies are not substituted merely because their histories are convenient.
For member i on trading date t, calculate its wealth relative R(i,t) = 100 × adjusted close(i,t) ÷ adjusted close(i,2023-01-03). The basket is B(t) = (1/5) × Σ R(i,t). This is equivalent to investing equal initial dollars in the five stocks on the base date and holding the resulting shares without rebalancing. It does not average daily returns and does not reset weights each day.
The benchmark is SPY, the SPDR S&P 500 ETF Trust, calculated as 100 × SPY adjusted close(t) ÷ SPY adjusted close(2023-01-03). SPY is labeled as an adjusted-close proxy rather than the official S&P 500 index. Using the provider’s adjusted-close field for both stocks and SPY avoids mixing dividend- and split-adjusted constituent series with a price-only index.
Yahoo Finance’s public chart API supplied daily adjusted closes for every instrument. The updater requested data through 2026-08-26, retained the intersection of dates with a finite positive value for all five constituents and SPY, and produced 915 dates from 2023-01-03 through 2026-08-26. No provider trading dates were omitted: all six instruments had valid adjusted closes on all 915 common dates. No values are imputed, forward-filled, or interpolated.
Adjusted closes are provider-derived market data, not official exchange closing records, and Yahoo does not publish the complete adjustment methodology or guarantee an immutable history or service level. Historical observations can be revised when corporate-action data change. Exact API URLs and the 2026-08-27 retrieval date are preserved below. The updater rejects nulls, nonpositive values, duplicate or unsorted dates, stale coverage, and missing values on common dates.
Split-event checks found continuous adjusted prices across NVIDIA’s 10-for-1 split on June 10, 2024 (1.007 close-to-close ratio) and Broadcom’s 10-for-1 split on July 15, 2024 (1.008 ratio), with no mechanical tenfold jump. Whole-company stock returns include non-AI businesses and market-wide factors; this concentrated, hindsight-selected comparison is not an investable index or investment advice.
Frequently asked questions
Which companies are in the fixed AI infrastructure basket?
NVIDIA, Broadcom, AMD, Microsoft, and TSMC ADR. Each receives 20% of initial dollars on January 3, 2023, and the shares are then held without rebalancing or replacement.
Why are neoclouds and consumer-internet companies excluded?
Public neoclouds do not have a common January 3, 2023 trading history, so they cannot be included in a series fixed to that date. Consumer-internet names are not substitutes for missing infrastructure exposure merely because their price data are available.
How is the basket index calculated?
Each member’s adjusted close is divided by its own January 3, 2023 adjusted close and multiplied by 100. The five resulting wealth relatives are averaged arithmetically. That represents equal initial dollars and buy-and-hold; it is not an average of daily returns or daily rebalancing.
What does the SPY benchmark represent?
SPY is an exchange-traded fund that tracks the S&P 500. Its provider-adjusted close is used as a compatible broad-market proxy and is labeled accordingly; the line is not the official S&P 500 index.
What does adjusted close include, and what are its limitations?
The chart uses Yahoo Finance’s adjusted-close field, which is provider-derived to account for splits and distributions. It is not an official exchange record, its methodology is not fully published, and historical values may be revised when the provider updates corporate actions.
How are missing dates handled?
Only dates with finite positive adjusted closes for all five stocks and SPY are retained. No values are filled or interpolated. For this retrieval, 915 dates were common and 0 provider date(s) were omitted.