---
title: "Precomputed toggle variants"
description: "Precomputed toggle variants are the finished result sets Fincanva computes for every combination of the three simulation assumptions in a single run."
canonical_url: "https://fincanva.com/glossary/precomputed-toggle-variants"
last_updated: "2026-10-06"
md_url: "https://fincanva.com/glossary/precomputed-toggle-variants.md"
---

# Precomputed toggle variants

Precomputed toggle variants are the finished result sets Fincanva computes for every combination of the three [simulation assumptions](/glossary/simulation-assumptions) — [Costs & interests](/glossary/costs-toggle), Taxes and [Reinvest profits](/glossary/reinvest-profits) — inside one single backtest, so flipping a toggle selects an already-computed result instead of starting a new one. Three on/off switches make eight combinations, and one backtest fills them.

**Also seen as:** toggle combinations, assumption variants

## How does Fincanva handle it?

- The toggles read a variant; they never queue a backtest, so they work identically on an old result and a fresh one, and never change the [strategy](/glossary/strategy)'s [status](/glossary/run-status).
- The rates behind the toggles are a different kind of change: editing a cost or tax rate is a settings change, which makes the strategy read **Needs re-run** and takes effect only after a re-run.
- Reinvest profits also selects which annualized figure is shown — [CAGR](/glossary/cagr) when it is on, [AAGR](/glossary/aagr) when it is off — and that swap is instant for the same reason.
- The Positions view is always served from the reinvesting, costs-off, taxes-off variant, whatever the toggles above the backtest results say: it answers "what would this strategy hold now", not "what did it net historically" ([Positions forced assumptions](/glossary/positions-forced-assumptions)).
- Because the variants belong to the backtest, a strategy whose result is reused rather than recomputed ([shared compute](/glossary/shared-compute)) arrives with all of them in place.

## What does it look like in practice?

You run a strategy once, with both cost and tax rates configured in your settings. The results open on the default view — gross of costs and tax, profits compounding. You flip **Taxes** on: the return, the annualized figure and the monthly table all drop to their after-tax values at once, because that variant was computed in the same backtest. You flip **Reinvest profits** off and the headline metric switches from CAGR to AAGR just as fast. Then you open Settings and change the capital-gains rate from 26% to 20%: nothing on the page moves, the strategy reads **Needs re-run**, and the new rate only appears after you re-run — the eight variants belong to the backtest that produced them, and a new rate needs a new one.

## Why does flipping an assumption toggle update instantly?

Because the result you switch to already exists. The three toggles are not inputs the [backtest](/glossary/backtest) is waiting on — they choose which finished variant is displayed, so switching one is a read, not a recomputation. A backtest therefore produces the gross view and the after-cost, after-tax and non-compounding views together, and the results page moves between them with no queue and no progress bar. That is why the after-tax curve appears the moment you ask for it.

## Why are there eight variants?

Three toggles with two states each give eight distinct combinations. Costs & interests, Taxes and Reinvest profits are each either on or off, and every way of setting the three of them together is one variant:

$$
2 \times 2 \times 2 = 2^3 = 8
$$

where: each factor is one assumption toggle with two states, on and off, and 8 is the number of distinct combinations of the three. All eight are produced when both costs and taxes are configured in your settings; fewer are produced when one of those sides is not configured, because a side with nothing set has nothing to switch between. Either way, every combination the app lets you select has a finished result behind it.

Fincanva is for education and illustration only. It is not personalised financial advice, and past or simulated results do not predict future ones. [Read the Terms Addendum](https://fincanva.com/terms/addendum#section-3)