Observatory · observe first

Where is market allocation moving?

See what is gaining weight, how quickly it is changing, and what is driving the move.

Historical time machine
Historical observation
20182026
S&P 500 matched members · 122 industries · Mar 2024Market-cap weights, not measured fund flows · pp = percentage points
Gaining weight
40
industries · over the last 12 months
Losing weight
64
industries · over the last 12 months
Accelerating
6
positive 3M gains are speeding up
Slowing
22
3M movement is easing, in either direction

What is driving the change?

12-month company attribution · a rising industry does not mean every company is gaining

Follow the hierarchy →
Concentrated

Most of this industry's gains came from a few companies.

Amazon+1.585 pp
All other companies-0.005 pp
100% of companies above their 6M weight average
See what contributed →
Concentrated

Most of this industry's losses came from a few companies.

Apple Inc.-1.558 pp
All other companies-0.025 pp
57% of companies above their 6M weight average
See what contributed →
Concentrated

Most of this industry's gains came from a few companies.

Walmart+0.893 pp
All other companies+0.026 pp
80% of companies above their 6M weight average
See what contributed →

Industry movements at a glance

Largest absolute allocation changes · descriptive observations, not rankings of investment merit

Watch the historical rotation →
IndustryMarket weight12M changeMovementParticipationWeight history · 24M
Technology Hardware, Storage & Peripherals
Lost weight for 4 consecutive months
7.61%-1.58 ppDeclining fasterConcentrated
Broadline Retail
Lost weight for 1 consecutive month
5.27%+1.58 ppAcceleratingConcentrated
Systems Software
Lost weight for 1 consecutive month
9.07%+1.47 ppSlowingConcentrated
Consumer Staples Merchandise Retail
Gained weight for 4 consecutive months
2.65%+0.92 ppAcceleratingConcentrated
Automobile Manufacturers
Lost weight for 1 consecutive month
1.84%-0.74 ppDeclining fasterConcentrated
Semiconductors
Gained weight for 5 consecutive months
4.31%+0.69 ppSlowingConcentrated
Diversified Banks
Gained weight for 1 consecutive month
3.85%+0.45 ppSlowingConcentrated
Application Software
Lost weight for 2 consecutive months
3.77%+0.45 ppReversing downwardBroad
Passenger Ground Transportation
Lost weight for 1 consecutive month
0.44%+0.44 ppSlowingConcentrated
Soft Drinks & Non-alcoholic Beverages
Gained weight for 1 consecutive month
1.60%-0.39 ppSlowingConcentrated
How are these descriptive states defined?

Gaining / losing: 12-month weight change above +0.005pp / below −0.005pp. Direction and speed are separate dimensions, not mutually exclusive recommendations.

Accelerating / slowing: compare the most recent 3M change with the preceding 3M change. Accelerating means a positive change speeds up by >0.02pp. Slowing means the magnitude of movement declines by >0.02pp. A falling industry can also slow.

Reversing: the last two 3M changes have opposite signs, outside a ±0.005pp tolerance. Persistence counts consecutive same-direction monthly changes.

Broad / concentrated: company attribution, not a market-cap concentration shortcut. Concentrated means the three largest same-direction contributors account for ≥70% of gross same-direction changes; otherwise broad requires ≥60% of constituents moving with the industry. Other cases are mixed.

Weights use matched S&P 500 members with SEC-reported shares and monthly prices. Companies without both data series are omitted; weights are normalised across matched members each month. These are simple market-cap estimates, not official float-adjusted S&P weights or measured investor flows.