Two reputable bodies measured the same month's passenger-vehicle growth and printed two different numbers. This brief decomposes the gap — what each number counts, and why they diverge.
For India passenger vehicles in April 2026, SIAM reported wholesale dispatches up +25.4% (to 437,312 units); FADA reported retail registrations up +12.21% (to 407,355 units). A 13.2-percentage-point gap (RAOSCAFF arithmetic) for the same vehicle category and month. Note: SIAM excludes certain OEM data; FADA covers 1,463–1,466 RTOs and excludes Telangana — the two bodies measure two different defined quantities over related but not identical national scopes. SIAM counts cars shipped to dealers; FADA counts cars registered to buyers. The gap is not an error — it is the brief.
In April 2026, India's passenger-vehicle market “grew strongly.” Two reputable bodies measured that growth. SIAM reported wholesale dispatches up +25.4%, to 437,312 units. FADA reported retail registrations up +12.21%, to 407,355 units. Same vehicle category, same month, a 13.2-percentage-point gap.
The two prints are not in conflict and neither is wrong. They answer different questions. SIAM counts vehicles shipped into the dealer channel — a factory-gate number. FADA counts vehicles registered out to end-buyers at the RTO via Vahan — the demand number. The ~29,957-unit aggregate arithmetic difference between them (RAOSCAFF arithmetic: 437,312 − 407,355) is consistent with channel fill — the two independently aggregated totals differ by this magnitude, indicating supply reached the dealer channel in excess of what registered to buyers in the same period.
This brief decomposes that gap. It is not a criticism of either body — both numbers are correct under their own definitions, and this brief ranks neither. The point is that “PV growth” is two facts, not one, and a reader who hears the dispatch rate as demand has read supply reaching the dealer as demand reaching the road.
Picture the channel as a pipe. A wide arrow of dispatches enters from the factory; a narrower arrow of registrations exits to buyers. The difference does not vanish — it pools on dealer lots as an inventory build. The aggregate arithmetic difference between the two independently measured flows is consistent with stock sitting in the channel.
The arrows are the two flows; the reservoir is the stock. A flow into the channel (dispatch) ran ahead of a flow out of it (registration), so the difference accumulated as a stock on the lot. That stock is visible in FADA's own figure: PV dealer inventory at 28–30 days in April 2026, above FADA's recommended 21-day benchmark. A meaningful part of the +25.4% dispatch surge is therefore still in the pipe — which is precisely why the retail flow grew at +12.21%, less than half the wholesale rate.
The gap is associated with three effects: a channel-fill wedge, an inventory build, and a lower base year. None of them is a data fault in either body.
The wedge is the population. “Wholesale dispatch” (OEM → dealer) and “retail registration” (dealer → end-buyer via Vahan) are two different defined quantities measuring one passenger-vehicle idea at different points in the channel. The April-2026 aggregate arithmetic difference between them is ~29,957 units (RAOSCAFF arithmetic: 437,312 − 407,355) — an indicator of supply that reached the dealer channel in excess of what registered to buyers in the same period. The inventory build is the amplifier. That difference is consistent with PV dealer inventory at 28–30 days vs FADA’s 21-day benchmark. The base year is the secondary amplifier. The two rates are computed off different April-2025 denominators — and a lower SIAM base lifts the SIAM rate mechanically.
Scope note: SIAM and FADA measure two different defined quantities measuring one passenger-vehicle idea. SIAM excludes certain OEM data; FADA covers 1,463–1,466 RTOs and excludes Telangana. Any wedge comparison between them reflects this scope difference in addition to the definitional difference between factory-gate dispatch and RTO registration.
| Effect | The figure | What it is |
|---|---|---|
| Channel-fill arithmetic difference · dominant | ~29,957 units | aggregate arithmetic difference between April-2026 wholesale dispatches and retail registrations (437,312 − 407,355, RAOSCAFF arithmetic) — an indicator of channel fill; sourced from two independently aggregated publisher totals, not a VIN-matched unit count |
| Inventory build · amplifier | 28–30 days | PV dealer inventory in April 2026 against FADA's recommended 21-day benchmark — the wedge accumulating as stock on the lot (FADA) |
| Base asymmetry · secondary amplifier | ~14,181 units | SIAM's official April-2025 base (3,48,847; SIAM press release via DD News, May 2025) sits below FADA's printed 363,028 — a smaller denominator lifts the SIAM rate (RAOSCAFF arithmetic on the gap: 363,028 − 348,847; both bases from primary sources) |
SIAM's own April-2026 prints corroborate an unusually low all-round April-2025 base — two-wheelers up +28.4% and three-wheelers up +32.8%. Lower base year, higher headline growth, mechanically. The 13.2-pp gap is associated with these three effects, not a fault in either number. The arithmetic difference, the rate gap, and the denominator gap are RAOSCAFF arithmetic on the two bodies’ published figures; the inventory and the FADA base are printed by FADA; the SIAM April-2025 base (3,48,847) is from the SIAM April-2025 press release (primary source).
If you read one thing: +25.4% is what factories shipped to dealers; +12.21% is what buyers took home — both are right, under their own definitions.
“India PV grew strongly in April 2026” is two facts, not one: +25.4% is what factories shipped to dealers, +12.21% is what buyers took home. Read the dispatch line (SIAM, 437,312 units) as production and the registration line (FADA, 407,355 units) as demand. Mirror Brief 22 ranks neither body and recommends no security — both numbers are correct under their own definitions, and the 13.2-percentage-point gap is associated with three effects: a channel-fill wedge (~29,957 units aggregate arithmetic difference, RAOSCAFF arithmetic), an inventory build (28–30 days vs FADA's 21-day benchmark), and a lower SIAM base year (official 3,48,847 vs FADA's printed 363,028; denominator gap ~14,181 units, RAOSCAFF arithmetic). GST 2.0 and the RBI rate stance appear here only as demand context FADA itself cites — not as a RAOSCAFF causal claim. The brief alleges nothing against SIAM or FADA, names neither as wrong, slow, or inferior, and offers no buy, sell, hold, or valuation view on any vehicle-maker, dealer, or auto stock.
Mirror format — RAOSCAFF anchors on each body's own released figures and decomposes the headline they print. Brief 22 is a twin-publisher brief, strictly anchored to April 2026, the latest month both SIAM and FADA have fully released. SIAM's wholesale dispatch figure (437,312 PV units, +25.4%) comes from the SIAM April-2026 press release (siam.in, 14 May 2026), with SIAM DG Rajesh Menon quoted; corroborated by DD News and IANS. SIAM's official April-2025 dispatch base (3,48,847 PV units) is sourced from the SIAM April-2025 press release, confirmed via DD News (15 May 2025). FADA's retail registration figure (407,355 PV units, +12.21%), its printed April-2025 base (363,028), the 28–30-day-vs-21-day inventory line, and its cited demand context come from FADA's April-2026 release via Outlook Business. The two metrics — wholesale dispatch (OEM → dealer) and retail registration (dealer → end-buyer via Vahan) — are never conflated; they measure different populations at different moments. Every figure traces to the companion FACTS.md, and the derived figures (the ~29,957-unit aggregate arithmetic difference, the 13.2-pp rate gap, and the ~14,181-unit denominator gap) are labelled RAOSCAFF arithmetic from the published figures; the SIAM April-2025 base (3,48,847) is sourced from primary SIAM publications, not derived.
Predict-not-recommend, and defamation-disciplined: the brief critiques the two metric definitions only — both bodies are correct under their own scope, and neither is named as wrong, slow, or inferior. Politically neutral: policy items (GST 2.0, the RBI rate stance) are reported strictly as FADA's own cited demand context, not as RAOSCAFF claims; the brief names no party, government, or minister, makes no causal market claim, and judges no policy as good or adequate. It cites no security and gives no buy, sell, hold, or valuation view. Limitations: May 2026 data was unpublished by both bodies at verification (2026-06-04) and is not cited; SIAM's April-2025 PV base of 3,48,847 units is sourced from the SIAM April-2025 press release (via DD News, 15 May 2025) and is used as a primary figure, not derived; and the brief does not decompose the per-OEM dispatch split or FADA's full inventory-value figure. Full source list and the verified figures behind every number are in FACTS.md § H.
All seven sources are SIAM- or FADA-primary or SIAM/FADA-anchored publications, fetched live 2026-06-04; SIAM's own press releases and FADA's own release carry the primary figures. Full citations and the verified figures behind every number in this brief are listed in the companion FACTS.md, § H.