Cohort Revenue by Order Month (Multi-Step SUMPRODUCT)

You're a finance analyst building a cohort retention table for the QBR. The order log at A2:D17 holds 16 orders with Customer (A), Order Date (B, full ISO date), Cohort (C, the customer's first-order month, pre-labeled), and Revenue (D).

You need total revenue for each (Cohort, Order Month) pair. The challenge: order month doesn't exist as its own column — you have to extract it from the full date. Three approaches:

• SUMPRODUCT with LEFT (recommended): =SUMPRODUCT(($C$2:$C$17=F2) * (LEFT($B$2:$B$17,7)=G2) * $D$2:$D$17). The LEFT(date,7) slices "2026-01-15" → "2026-01" inline, so SUMPRODUCT can multiply the boolean masks.
• Helper column: add a column that computes =LEFT(B2,7) for every row, then SUMIFS on (Cohort, helper).
• TEXT-based: if dates are stored as Excel date numbers rather than ISO text, use TEXT(B2:B17,"yyyy-mm") instead of LEFT.

Three (Cohort, Order Month) lookups are pre-populated in F2:G4.

Your task:

1. In column H (Revenue), write a formula that returns total revenue for each (Cohort, Order Month) pair.

Graded cells: H2, H3, H4.