# Diesel prices changed this year. Does that distort a spend-based emissions estimate?

Canonical: https://senseible.earth/answers/diesel-price-change-and-spend-based-estimates

Yes. If you estimate from rupees, a price rise looks like more fuel and a price cut looks like less. Convert spend to litres with the price on each invoice date, or better, use the litres printed on the invoice. Emissions follow litres, not rupees.

## Why it matters

Spend-based factors assume a fixed price. When the pump price moves, the same litres produce a different rupee total and a different estimate.

## Fix it

- Use litres from the invoice where shown.
- Otherwise divide spend by the pump price on that date.
- Note which months were estimated.

## Same fuel, two estimates

- Rs 9,00,000 at Rs 90 per litre = 10,000 L
- Rs 9,00,000 at Rs 95 per litre = 9,474 L
- Using 90 overstates by 526 L, about 1,410 kg CO2

## What Senseible does here

Senseible reads quantities, dates and units from your bills and invoices and shows the factor and source used on every line.

- [Spend-based Scope 3 and inflation](https://senseible.earth/answers/spend-based-scope-3-gst-inflation-currency)
- [Fuel bill with only rupees](https://senseible.earth/answers/fuel-invoice-amount-only-no-litres)

Sources: [GHG Protocol Corporate Standard](https://ghgprotocol.org/corporate-standard), [IPCC 2006 Guidelines, Volume 2: Energy](https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol2.html)

Last reviewed 2026-10-22.