📌 Stage 2 · People and Revenue · Revenue Plan · drivers and seasonal index · 35–45 min
Clients × fee × season, one row at a time
Learning goals
- Split revenue into a retainer engine and a project engine
- Apply the seasonal index to both engines with cell formulas
- Read the FY totals and confirm the revenue plan ties to the P&L
- Explain why the index row must average 100%
Concepts
Two revenue engines
The studio sells two things. Retainers are monthly service agreements: a small number of clients billed every month at a fixed fee — predictable revenue. Projects are one-off brand and web engagements: a count per month at a blended average fee — seasonal revenue.
Under Base, three retainer clients pay $6,500.00 each per month ($234,000.00 for the year) and four projects a month at $9,500.00 average ($456,000.00), for $690,000.00 of FY2026 billings. The Revenue Plan builds each engine as its own row so the P&L can report the mix.
The seasonal index
Row 6 of the Revenue Plan is a typed index where 100% is an average month: January 0.85, February 0.90, March through May 1.05–1.10, summer 0.80–0.95, September through December back to 1.05–1.15. The twelve values average exactly 100% — check it yourself:
=IF(COUNT(C6:N6)=0,0,AVERAGE(C6:N6))Revenue Plan O6: the FY column averages the twelve monthly indices and returns 100%. If the row is empty the guard returns 0 instead of #DIV/0!. The average must stay 100%, or the year is silently re-based.
💡 Tips:
- Type the index from your own history: last year's billings divided by the average month is a defensible starting point.
Retainer and project billings
Each billing row multiplies its drivers by the month's index — and pulls every driver from the Assumptions Active column, so the scenario switch moves both engines:
=Assumptions!$F$14*Assumptions!$F$15*C6Revenue Plan C8 (January retainer billings): 3 clients × $6,500.00 × 0.85 = $16,575.00. The FY total in O8 is $234,000.00.
=Assumptions!$F$16*Assumptions!$F$17*C6Revenue Plan C9 (January project billings): 4 engagements × $9,500.00 × 0.85 = $32,300.00. The FY total in O9 is $456,000.00.
Total billings and the tie-out
Row 10 adds the two engines, and column O sums the twelve months:
=C8+C9Revenue Plan C10: January total billings $16,575.00 + $32,300.00 = $48,875.00. O10 sums to the FY figure $690,000.00, which Monthly P&L row 8 links to as total revenue.
💡 Tips:
- Retainers are 34% of the year (O8/O10). The higher that share, the calmer the cash flow — a useful fact when the studio weighs a retainer push against project work.
Practice
Fixed case: Harbor Creative Studio LLC, a four-person design studio in Austin, Texas, planning calendar year 2026. Cached numbers are the Base scenario. Pale-green cells are formulas; white cells are typed inputs. The exercise opens on the sheet this lesson teaches. Cell C8 (January retainer billings) is blank: retype the driver multiplication.
- Open Revenue Plan — The exercise opens on Revenue Plan. Row 6 is the seasonal index (typed); row 8 is retainer billings; row 9 is project billings; row 10 is total billings.
- Retype the retainer formula in C8 — Cell C8 is empty. Type =Assumptions!$F$14Assumptions!$F$15C6 and confirm: it should return $16,575.00 (3 × $6,500.00 × 0.85).
- Read the two engines — O8 (FY retainers) should read $234,000.00 and O9 (FY projects) $456,000.00. Scan the peak months: the March-to-May and September-to-December blocks each bill above $60,000.00; July and August are the trough near $46,000.00.
- Check the index average — O6 should read 100%. If it does not, the index row was mistyped — that is the built-in check for the whole revenue plan.
- Confirm the FY tie — O10 should read $690,000.00. Open Monthly P&L: C8 (January revenue) links to this sheet's C10 and reads $48,875.00, and O8 reads the same $690,000.00.
Online exercise
The spreadsheet below is editable — follow the practice steps right on this page. Steps that need ribbon menus should be done in your own Excel with the downloadable practice file.
Checklist
Work through each item; when every box passes, this lesson is done:
- ☐ Retyped the retainer formula in C8 and it returned $16,575.00
- ☐ O8 reads $234,000.00 and O9 reads $456,000.00; O10 reads the FY total $690,000.00
- ☐ O6 confirms the seasonal index averages 100%
- ☐ Can state the retainer share of revenue and why it matters for cash flow