Market education

Not yet editorially reviewed

Understanding Value History and Market Movement

Read approved states, calculate change and interpret sparse history without turning a baseline into a trend or a flat market claim.

Value history describes approved states recorded at particular times. It does not reconstruct every trade or every price between those dates.

Prepared by:
Trade Index draft, prepared with Codex
Reviewer:
Pending editorial review
Published:
Not published

Draft guidance awaiting human editorial review. No publication or review date has been assigned.

Draft guideEvidence and limitations

One state establishes a starting point

The July 2 Shadow Dragon baseline stores 2,450 points. On its own, it gives a dated reference. It cannot show an increase, decrease or historical range.

Do not draw a flat line across later dates when no later state was approved. That would replace missing observations with invented history.

Two approved states support a comparison

Two compatible states allow an absolute change and a percentage change. Subtract the earlier value from the later value; divide that difference by the earlier value for the percentage.

The zero-baseline case has no defined percentage under this rule. Report the absolute change and leave the percentage unavailable. Do not substitute zero percent.

A synthetic example teaches the arithmetic

Suppose an illustrative record changed from 100 to 120 in the same unit. The change is +20 and +20%. These numbers are teaching inputs, not a Trade Index market event.

Changing from 120 back to 100 is -20, but about -16.7%. The percentage changes because its reference value changes.

Three states can support a basic chart

With three or more compatible approved states, a chart can show the recorded path. Pair it with a table of dates and values so the result is readable without the graphic.

Do not label the intervals as daily prices when reviews were irregular. The connecting line does not prove what happened between observations.

Stability requires more than sparse history

Five or more approved states across multiple review periods can make a stability calculation possible only if its method is documented. Count, duration, unit consistency and gaps all matter.

A flat set of infrequent observations can miss changes between checks. Do not describe baseline-only items as the most stable tracked items.

Check the note behind the movement

Read the approved editorial rationale. A changed value does not explain its own cause, and a source conflict is not evidence of popularity rising.

Market Pulse can identify confirmed recorded changes for a window. Keep its scope attached to the result instead of describing those records as the whole game market.

Frequently Asked Questions

Frequently asked questions

Why does an item have no history chart?

It may have too few compatible approved states. A baseline or change table can convey the evidence without implying a trend.

Can a source proposal appear as movement?

Pending or rejected proposals are not approved movement. Only compatible approved states belong in the published change calculation.

Can I calculate a percentage from a zero starting value?

Not with the stated percentage-change formula. Report the absolute difference and leave the percentage unavailable.

Does a straight line between reviews show daily prices?

No. It connects recorded approved states. It does not supply observations for the days between those reviews.

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