At a glance
A 90-day sparkline of average EasyPost label cost per parcel. Where Avg Shipping Cost gives the single headline number, this card shows the shape of it over the quarter, so a slow upward drift, a step change after a carrier rate rise, or a seasonal swing is visible at a glance rather than hidden in a point-in-time figure.
What it tracks
Grounded in the card’sdetail (“Cost Per Shipment Trend for the selected period.”): each point on the sparkline is the average billed cost per EasyPost parcel for that day or week (SUM(selected_rate + surcharges + per-label fee) / COUNT(shipments)), read from the Shipments API (GET /v2/shipments) over the trailing 90 days. The trend is what makes a cost creep actionable: a single high reading is noise, but a sustained climb is a signal. The common shapes are a step up after an annual carrier general rate increase (GRI), a gradual drift as parcel mix shifts to heavier items or further zones, a peak-season bulge from surcharges, or a welcome step down after a successful carrier renegotiation or a rate-shop rule change. This card carries no alert; it is the context behind the +10% vsP alert on Avg Shipping Cost. Read it next to Cost by Zone and Shipments by Underlying Carrier to attribute a move to a zone shift or a carrier-mix change, and next to Carrier-Mix Savings vs Single-Carrier Baseline to see whether rate shopping is offsetting the rise.